crab dissertation

7/31/2019 Crab Dissertation

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http://www.youtube.com/watch?v=v217vghCG7g&list=PLED5E234FBC30A8D5&index=3&feature=plpp_video


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Study of Crab DissertationContent Details

Objective: - Recreate crab in CG with photo-realistic look, which includes anatomy, behavior,

Movements. And integrate seamlessly into live action footage.

Group members: Junaid Mirza (Modeling)

Shruthi (Animator)

Lal Bahadur (Animator)

Ragatej (vfx)

Vijay Parthap (vfx)

1. History of Crab (vijay prathap)

1.1 Entire history

1.2 Mythological status 1.3 Social role

1.4 Role in stories

2.Breeds of Crab /type of Crab seen in general (ragtej)

2.1 Differentiate between genders of a crab on the basis of their appearance.

2.2 Differentiate between the breeds of Crab on the basis of

their appearance.

2.3 Names based on ages, gender, regions food.

3. Biology of Crab (mirza)

3.1 Lifespan of crab

3.2 Size and measurement

3.3 Colors and markings

3.4 Reproduction and development

4. Anatomy (Lalu)

4.1 Skeletal system with naming

4.2 Eye, Mouth & ear Systems& sense organs

4.3 Body organs

4.4 Study of Muscular system & their movements (walk, run, standing on eight legs,

and others..

4.5 Look and feel details (defuse, secular, etc,.) of different.


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5 . Movement (Vemula shruthi)

5.1 How its walks

5.2 How it eats

5.3 How it attacks 5.4 Influence of the bones on the muscle when movement takes place


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Social role:

Social Networking Helps Crabs:

Everyone wants to live in the nicest possible house, ideally with regular upgrades. A

recent study by biologists at Tufts University's School of Arts and Sciences and the New

England Aquarium reveals that hermit crabs may locate new and improved housing

using previously unknown social networking skills

The scientists combined field studies, lab experiments and computer models to uncover

some surprising new tricks that could lead to better house-hunting strategies for

humans and hermit crabs alike. Their research, published in the May/June 2010 issue ofthe journal Behavioral Ecology (available online on April 1), reveals that, contrary to

their name, hermit crabs often find the best new shells when they gather together.

Hermit crabs have an unusual lifestyle because they require empty snail shells for

shelter. They need to regularly seek new shells as they grow bigger throughout their

lives. "Hermit crabs are really picky about real estate because they're constantly getting

thrown back into the housing market," says Randi Rotjan, leader of the research team

and a co-author with Sara Lewis, professor of biology at Tufts University's School of Arts

and Sciences.

Rotjan studied with Lewis to earn her Ph.D. from Tufts Graduate School of Arts and

Sciences in 2007 and is now a research scientist at the New England Aquarium. Starting

during Rotjan's graduate school days, Rotjan and Lewis have collaborated to gain a

better understanding of social interactions among hermit crabs.

Often there aren't enough suitable shells to go around and some hermit crabs have to

go naked. The soft, exposed abdomen of these homeless crabs makes them more

vulnerable to predators. "I've seen hermit crabs dragging around in bottle caps and even

ballpoint pen tops. It's pathetic," says Lewis, senior author on the Behavioral Ecology

paper.


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So, how do hermit crabs win this life-or-death shell game? One previously identified

strategy that apparently helps each hermit crab find the very best shell is joining a lively

group activity known as a synchronous vacancy chain. When a new shell becomes

available, crabs gather around it and queue up in a line from largest to smallest. Oncethe largest crab moves into the vacant shell, each crab in the queue swiftly switches into

the newly vacated shell right in front of them. As a result, a single vacant shell kicks off

an entire chain of shell vacancies that ultimately leads to many crabs getting new, and

generally improved, housing.

Hermits Show New Social Behaviors

By seeding vacant shells into field populations and staying up all night to see what

happened, the scientists discovered some previously unknown hermit crab behaviors.

When a hermit crab discovers an empty but oversized shell, it waits nearby rather than

simply walking away. Once a small group gathers, crabs begin piggybacking by holding

onto the shell of a larger crab and riding along. Such waiting and piggybacking behaviors

seem to increase the chances that a synchronous vacancy chain will happen. "They

spend hours queuing up, and then the chain fires off in seconds, just like a line of

dominoes," says Rotjan. Computer models populated with virtual hermit crabs and

shells confirmed that synchronous vacancy chains depend not only on crab density, but

also on how long crabs are programmed to wait near an unsuitable shell.

According to Rotjan, the same kind of synchronous vacancy chain can occur with anyanimal that relies on discrete and reusable resources, such as anemone-dwelling fish

and hole-nesting woodpeckers. Studying vacancy chains in hermit crabs might even lend

new perspective on human behaviors, since people regularly participate in synchronous

vacancy chains. For example, every September 1, neighborhood streets in Boston,

Mass., are clogged with rental trucks and moving vans. This signals that the city's many

students are participating in synchronous vacancy chains on this popular start date for

annual leases. Like hermit crabs, these savvy apartment-hunters carefully assess all the

housing options beforehand, and line up on September 1 to switch into their ideal

homes.

Social networking sites like Craigslist and Facebook have made it much easier for people

to assess housing options and coordinate their moving dates. Hermit crabs must instead

resort to queuing up as they wait near empty shells. But in the end, social networking

leads to better housing for everyone.


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Role in stories :

1.http://www.youtube.com/results?search=Search&resnum=0&oi=spell&search_query

=tales+of+crab&spell=1&suggested_categories=24%2C20%2C22%2C26&sa=X

2.http://www.indianhindunames.com/panchatantra-stories-heron-crab.htm

Panchatantra story-The heron and the crab

moral stories

Long time ago there lived a heron by the side of

a pond. It was a lazy creature and once devised

a plan to get supply of fish without doing much

work. He went to the side of the pond and put

on a gloomy face without attempting to catch

any fish. The pond was also inhabited by a crab,

which was wise and often helped the fish in the

pond. On seeing the gloomy heron, the crabasked her what the matter was.

The heron said, "Alas! I am worried that the pond is going to be soon devoid of any fish,

which are in turn my source of food. I overheard a group of fishermen talking about

catching all the fish in this pond. But I know of a pond somewhat far away, where all the

fish will be safe. If the fishes are interested, i can carry a few each day to the other pond

where they will be safe."

All the fish were eager to make use of the heron in reaching the safer destination. So

everyday some of them volunteer to go with the heron. The heron took some fish each

day in the beak, and on reaching a large rock used to eat all the fish and leave the bones

of the fish at the rock. This way, she was able to get a continuous supply of fish at no

effort at all. In the end, the curiosity got the better of the crab, and one day it

volunteered to go with the fish. When it got closer to the rock, it realized the foul play

the heron had been playing on the poor fish. Enraged, it tightened its claws around the


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neck of the heron and snapped the head of the heron off. The heron thus died a selfish

death. The crab crept back to the pond and told all the fish about the lies the heron had

been telling.

Story moral: Excess of Greed is harmful.

THE STORY OF THE CRAB BUCKET

One time a man was walking along the beach and say another man fishing in the surf

with a bait bucket beside him. As he drew closer, he saw that the bait bucket had no lid

and had live crabs inside.

"Why don't you cover your bait bucket so the crabs won't escape?", he said.

"You don't understand.", the man replied, "If there is one crab in the bucket it would

surely crawl out very quickly. However, when there are many crabs in the bucket, if one

tries to crawl up the side, the others grab hold of it and pull it back down so that it will

share the same fate as the rest of them."

So it is with people. If one tries to do something different, get better grades, improve

herself, escape her environment, or dream big dreams, other people will try to drag her

back down to share their fate.

Moral of the story: Ignore the crabs. Charge ahead and do what is right for you. It may

not be easy and you may not succeed as much as you like, but you will NEVER share the

same fate as those never try.

We have been enriched by the talents of people who have had less than "perfect"

bodies, whether by birth, accident or disease - Helen Keller, F.D. Roosevelt, Stephen

Hawking, George Bush, Stevie Wonder, Christopher Reeve, to name just a few. Theychose to "climb the crab bucket" instead of listening to others.


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Differentiate between genders of a crab on the basis of their appearance:

Male Crab

The Male crab is also known as Jimmyhas blue claws and an underside "apron"

which looks like an upside-down T or the

"Washington Monument." Large male

crabs are also called channelers.

Unlike female crabs, there is no easy wayto tell the sexual maturity of the male.

However, upon a very close inspection, you will

note that the apron of the adolescent male is tightly

sealed to his body whereas the adult male is free to

open his apron

Female Crab

A mature female Crab is also known asSOOK . She has a widened apron with a

semicircular bell shape that looks like the

U.S. Capitol building.

Her broadly rounded abdomen is free toopen and is not sealed shut as before.

She must open her apron in order to

mate and to carry eggs


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Immature (adolescent) Female Crab

The she-crab or immature (adolescent) femalecrab is also known as SALLY.

She can easily identified as she having aninverted "V" or triangular shaped apron. And

she is having two red-tipped claws. Her apron

is tightly

sealed to her

body and

does notopen since

she cannot mate or carry eggs.

Sponge Crab

Pregnant Crab is also known as SPONGE CRAB".

They carry fertilized eggs under their abdomen.

From a distance these eggs resemble a sponge,

hence the term it called as "sponge" crab. It takes

about two weeks for the eggs to "ripen" and be

released into the water to hatch.


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Differentiate between the breeds of Crab on the basis of

their appearance:

Crab Varieties

There are over 4,400 varieties of crabs. Crabs are of the order Decapoda which

covers a large variety of different crustaceans. The word crab comes from the Middle

English. The crab is one of the oldest species on earth. The horseshoe crab dates back

over 200 million years and is literally a living fossil.

The majority of edible crabs have five pairs of legs, with the front legs being larger

pinchers. Out of the 4,400 varieties of crab, most are found in North America in both

salt and fresh water.

Names based on ages, gender, regions food:

BLUE CRAB :

Blue Crab: Its latin name, Calinectes sapidus,

means "beautiful swimmer," and it is indeed a

beautiful blue-green color. The most prolific

species on the East Coast of the US, this is the

crab which also gives us soft-shell crabs. They

range in size from 3-1/2 inches up to 5-1/2

inches .


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DUNGENESS CRAB :

Dungeness crab: Latin name Cancer magister, this crab

is found in coastal waters from Alaska, united states to

Baja, Mexico. This large crab usually weighs in from 1-

3/4 to 4 pounds, and is brown to purple in color. It is

named for the former small town of Dungeness on the

Olympic peninsula in ,Washington State US. The

carapace width of mature Dungeness crabs may reach

25 centimeters (9.8 in) in some areas off the coast of

Washington, but are typically under 20 centimeters

(7.9 in). they are a popular delicacy, and are the most

commercially important crab in the pacific northwest ,

as well as the western states generally.

HORSESHOE CRAB :

Horseshoe Crab: Latin name Limulus

polyphemus, this crab is named for its

resemblance in shape to a horseshoe. It is

considered a living fossil, tracing its roots back

some 500 million years. It is found along the

Atlantic coast from Nova Scotia to the Yucatan and

along Asian coasts from Japan and the Philippines

to India. Horseshoe crabs are arthropods that live

primarily in shallow ocean waters on soft sandy ormuddy bottoms. They will occasionally come on

shore for mating. They are commonly used as bait

and in fertilizer. hey have five pairs of legs for

walking, swimming and moving food into the


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mouth. The long, straight, rigid tails can be used to flip themselves over if they are

turned upside down, so a horseshoe crab with a broken tail is more susceptible to

desiccation.Females are larger than male Horseshoe crabs.

KING CRAB

King Crab: Latin name Paralithodes camtschaticus,

This giant crab is also often called "Alaskan King

crab," "Japanese crab," and "Russian crab" due to its

size, which can reach up to 25 pounds and measureup to 10 feet. It may be large, but only about one-

fourth is edible, primarily the legs and claws. Only

males are harvested. King crabs are generally

thought to be derived from hermit crab-like

ancestors, which may explain the asymmetry still

found in the adult forms. Although some doubt still

exists about this theory, king crabs are the most

widely quoted example of carcinisation among the

Decapoda. This is also known as Stone Crab.

KING CRAB :Stone Crab: Latin name Menippe mercenaria,

it is also called "moro" or "morro" crab. It has

large, very hard claws that are prized for their

meat. Most of the harvest comes from

Florida, US.


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Description:

The stone crab's carapace (shell) is 3 to 3.5 inches (7.6 to 8.9 cm) long and about 4

inches (10 cm) wide. Stone crabs are brownish red with gray spots and tan underneath,

and have large and unequally-sized pincers with black tips. Females have a larger

carapace (the top outer shell), but males usually have larger claws than females.

Life History:

Stone crabs prefer to feed on oysters and other small mollusks, polychaete worms, and

other crustaceans. They will also occasionally eat seagrass and carrion (remains of dead

animals). Predators that feed on stone crabs include horse conch, grouper, sea turtles,

cobia, octopi, and humans.

Sexual maturity is reached at one year. Their long spawning season lasts all spring and

summer, during which time females produce 500,000 to 1 million eggs. The larvae go

through six stages in about 36 days before emerging as juvenile stone crabs. Their

lifespan is seven to eight years.

The male stone crab must wait for the female to shed her exoskeleton before they can

mate. After mating, the male will stay to help protect the female for several hours to

several days. The female will spawn four to six times each season. Adult stone crabs

make burrows in mud or sand below the low tide line, lying in wait for prey.

The stone crab loses its limbs easily to escape from predators or tight spaces, but their

limbs will grow back. When a claw is broken in the right place, the wound will quickly

heal itself and very little blood is lost. If, however, the claw is broken in the wrong place,more blood is lost and the crab's chances of survival are much lower. It only takes about

one year for the claw to grow back to its normal size. Each time the crab molts its

exoskeleton, the new claw grows larger.

The larger of the two claws is called the "crusher claw". The smaller claw is called the

"pincer claw". If the larger crusher claw is on the right side of the crab's body, the crab is

"right handed". If the crusher claw is on the left side of the crab's body, it is "left

handed". Since crabs' eyes are on stalks, they can see 360. A large crab claw can weigh

up to half a pound.

Habitat.

Stone crabs prefer bottoms of bays, oyster reefs and rock jetties where they can burrow

or find refuge from predators. Juveniles do not usually dig burrows, but instead hide

among rocks or in seagrass beds.


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Lifespan of crab :

Shells and shell competition

Hermit crabs fighting over a shell

As hermit crabs grow they require larger shells. Since suitable intact gastropod shells are

sometimes a limited resource, there is often vigorous competition among hermit crabs

for shells. The availability of empty shells at any given place depends on the relative

abundance of gastropods and hermit crabs, matched for size. An equally important issue

is the population of organisms that prey upon gastropods and leave the shells intact.[8]

Hermit crabs that are kept together may fight or kill a competitor to gain access to the

shell they favor. However, if the crabs vary significantly in size, the occurrence of fights

over empty shells will decrease or remain non-existent.[7]

A hermit crab with a shell that is too small cannot grow as fast as those with well-fitting

shells, and is more likely to be eaten if it cannot retract completely into the shell.[9]

For some larger marine species, supporting one or more sea anemones on the shell can

scare away predators. The sea anemone benefits, because it is in position to consume

fragments of the hermit crab's meals.

Biology

The edible crab, Cancer pagurus, is found only in European waters. It occurs all round

the British coast and is found in abundance usually where the sea bed is rugged.

Despite its reputation as a scavenger, the crab feeds mainly on living food, including fish,

marine worms and shellfish such as mussels, which are crushed in its powerful claws.
http://en.wikipedia.org/wiki/Gastropod_shellhttp://en.wikipedia.org/wiki/Hermit_crab#cite_note-7http://en.wikipedia.org/wiki/Hermit_crab#cite_note-7http://en.wikipedia.org/wiki/Hermit_crab#cite_note-7http://en.wikipedia.org/wiki/Hermit_crab#cite_note-Rotjan-6http://en.wikipedia.org/wiki/Hermit_crab#cite_note-Rotjan-6http://en.wikipedia.org/wiki/Hermit_crab#cite_note-Rotjan-6http://en.wikipedia.org/wiki/Hermit_crab#cite_note-8http://en.wikipedia.org/wiki/Hermit_crab#cite_note-8http://en.wikipedia.org/wiki/Hermit_crab#cite_note-8http://en.wikipedia.org/wiki/Marine_(ocean)http://en.wikipedia.org/wiki/Sea_anemoneshttp://en.wikipedia.org/wiki/Sea_anemoneshttp://en.wikipedia.org/wiki/Marine_(ocean)http://en.wikipedia.org/wiki/Hermit_crab#cite_note-8http://en.wikipedia.org/wiki/Hermit_crab#cite_note-Rotjan-6http://en.wikipedia.org/wiki/Hermit_crab#cite_note-7http://en.wikipedia.org/wiki/Gastropod_shell


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The crabs keen sense of smell and its voracity account for the ease with which it is

caught in baited traps.

The crab is encased in a hard, rigid shell of fixed shape which must be cast off at

intervals and replaced by a larger one so that the crab may have room to grow; this

process is known as moulting or ecdysis. In Britain the main moulting period is from Julyto October; the females start moulting in July, followed by the males a month or so

later. At this time the crab seeks shelter among the rocks. The shell cracks along a

precise line dividing the upper and lower halves, and the soft crab inside slowly backs

out through the gap. It then absorbs water and swells, increasing in size across the back

by as much as 20 to 30 per cent in one moult. Males appear to grow slightly more during

a moult than females, but moult less frequently after they reach a size of 4 inches. On

average, a 3 -inch male on the east coast will reach 4 inches in one moult and 5

inches in the next.

After a moult has been completed the shell slowly hardens and no further increase in

size will occur until the next moult, although the shell will not be completely hardened

for two or three months. Moulting takes place at frequent intervals during the crabs

early life, but after it has reached a size of 5 inches moulting takes place about once

every two years. It is not possible to state the age of a crab with accuracy, since no part

of the body gives a reliable guide, but on average a 4 -inch crab is about four to five

years old. Most female crabs are mature by the time they measure 5 inches across the

back, whilst males reach maturity at a slightly smaller size.

The sex of a crab can easily be determined; the female or hen crab has a broad beehive-

shaped abdomen or apron, whereas the male or cock crab has a narrow abdomen which

fits tightly to the body (figure 2). The claws of the male are also larger than those of a

female of the same size.

Mating occurs in inshore waters during the summer, immediately after the female crab

has moulted and while it is in the soft-shelled condition. Prior to the moult, and for a

period of up to a fortnight after, the female is attended by a hard-shelled male.

Immediately the female has cast her shell mating takes place and the male sperms are

introduced into the females two sperm sacs. One supply of sperm may fertilize two ormore batches of eggs in subsequent years, and the majority of females that mate in July

or August will spawn, that is carry eggs, in November or December of the same year, but

in some cases spawning is delayed until the next winter. Crabs usually select a soft sea

bed for spawning, often in deep water, and the eggs remain attached to the swimmerets

on the abdomen of the parent for about seven months. A crab with eggs is sometimes


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called a berried crab and the number of eggs carried can vary from half a million on a 5-

inch crab to three million on a 7-inch one.

In the spring and summer following spawning the berried females move inshore, where

the eggs hatch; the young crabs at first have a shrimp-like appearance and form part of

the free-floating plankton. This period is believed to last about a month, and during thistime the larval crab will probably drift to new grounds away from the hatching area. It

finally settles on the sea bed and assumes the adult form when it is about inch in size.

Tagging experiments have shown that on the east coast of Britain mature female crabs

can move considerable distances, mainly in a northerly direction. Crabs released off

Whitby, Yorkshire, have been recaptured along the Scottish coast, having moved

distances of between 180 and 200 miles in twelve to eighteen months. These migrations

are associated with the offshore movement of females for spawning. Male crabs rarely

moved far from the point of release.


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FIGURE 1. Parts of the edible crab


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FIGURE 2. External features of male and female crabs


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Size and measurement :

Gecarcinus quadratus, a land crab from

Central and South America

Crabs are generally covered with a thick

exoskeleton, and armed with a single pair of

chelae (claws). Crabs are found in all of the

world's oceans, while many crabs live in fresh

water and on land, particularly in tropical

regions. Crabs vary in size from the pea crab, a few millimetres wide, to the Japanese

spider crab, with a leg span of up to 4 metres (13 ft).[4]

About 850 species of crab are freshwater, terrestrial or semi-terrestrial species;[5]

they

are found throughout the world's tropical and semi-tropical regions. They were

previously thought to be a monophyletic group, but are now believed to represent at

least two distinct lineages, one in the Old World and one in the New World.[6]

The earliest unambiguous crab fossils date from the Jurassic,[7]

although Carboniferous

Imocaris, known only from its carapace, may be a primitive crab.[8]

The radiation of

crabs in the Cretaceous and afterward may be linked either to the break-up of

Gondwana or to the concurrent radiation ofbony fish, crabs' main predators.[9]

Life cycle

Coconut crabs mate frequently and quickly on dry land in the period from May to

September, especially between early June and late August.[20]

Male coconut crabs have

spermatophores and deposit a mass of spermatophores on the abdomen of the

female;[21]

the abdomen opens at the base of the third pereiopods, and fertilisation is

thought to occur on the external surface of the abdomen as the eggs pass through the

spermatophore mass.[22]

The extrusion of eggs occurs on land in crevices or burrows

near the shore.[23]Shortly thereafter, the female lays her eggs and glues them to the

underside of her abdomen, carrying the fertilised eggs underneath her body for a few

months. At the time of hatching, the female coconut crab releases the eggs into the

ocean.[22]

This usually takes place on rocky shores at dusk, especially when this coincides

with high tide.[24]

The empty egg cases remain on the female's body after the larvae

have been released, and the female eats the egg cases within a few days.[24]
http://en.wikipedia.org/wiki/Halloween_crabhttp://en.wikipedia.org/wiki/Halloween_crabhttp://en.wikipedia.org/wiki/Land_crabhttp://en.wikipedia.org/wiki/Central_Americahttp://en.wikipedia.org/wiki/South_Americahttp://en.wikipedia.org/wiki/Exoskeletonhttp://en.wikipedia.org/wiki/Clawhttp://en.wikipedia.org/wiki/Freshwaterhttp://en.wikipedia.org/wiki/Freshwaterhttp://en.wikipedia.org/wiki/Land_crabhttp://en.wikipedia.org/wiki/Tropicalhttp://en.wikipedia.org/wiki/Pea_crabhttp://en.wikipedia.org/wiki/Japanese_spider_crabhttp://en.wikipedia.org/wiki/Japanese_spider_crabhttp://en.wikipedia.org/wiki/Crab#cite_note-3http://en.wikipedia.org/wiki/Crab#cite_note-3http://en.wikipedia.org/wiki/Crab#cite_note-3http://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Crab#cite_note-4http://en.wikipedia.org/wiki/Crab#cite_note-4http://en.wikipedia.org/wiki/Crab#cite_note-4http://en.wikipedia.org/wiki/Subtropicshttp://en.wikipedia.org/wiki/Monophyletic_grouphttp://en.wikipedia.org/wiki/Lineage_(evolution)http://en.wikipedia.org/wiki/Old_Worldhttp://en.wikipedia.org/wiki/New_Worldhttp://en.wikipedia.org/wiki/Crab#cite_note-5http://en.wikipedia.org/wiki/Crab#cite_note-5http://en.wikipedia.org/wiki/Crab#cite_note-5http://en.wikipedia.org/wiki/Fossilhttp://en.wikipedia.org/wiki/Jurassichttp://en.wikipedia.org/wiki/Crab#cite_note-6http://en.wikipedia.org/wiki/Crab#cite_note-6http://en.wikipedia.org/wiki/Crab#cite_note-6http://en.wikipedia.org/wiki/Carboniferoushttp://en.wikipedia.org/wiki/Carapacehttp://en.wikipedia.org/wiki/Crab#cite_note-7http://en.wikipedia.org/wiki/Crab#cite_note-7http://en.wikipedia.org/wiki/Crab#cite_note-7http://en.wikipedia.org/wiki/Adaptive_radiationhttp://en.wikipedia.org/wiki/Cretaceoushttp://en.wikipedia.org/wiki/Gondwanahttp://en.wikipedia.org/wiki/Osteichthyeshttp://en.wikipedia.org/wiki/Predatorhttp://en.wikipedia.org/wiki/Crab#cite_note-8http://en.wikipedia.org/wiki/Crab#cite_note-8http://en.wikipedia.org/wiki/Crab#cite_note-8http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2008b-19http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2008b-19http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2008b-19http://en.wikipedia.org/wiki/Spermatophorehttp://en.wikipedia.org/wiki/Coconut_crab#cite_note-Tudge1991-20http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Tudge1991-20http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Tudge1991-20http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2009-22http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2009-22http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2009-22http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Tidehttp://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Fletcher_656-23http://en.wikipedia.org/wiki/Tidehttp://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2009-22http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Schiller-21http://en.wikipedia.org/wiki/Coconut_crab#cite_note-Tudge1991-20http://en.wikipedia.org/wiki/Spermatophorehttp://en.wikipedia.org/wiki/Coconut_crab#cite_note-Sato2008b-19http://en.wikipedia.org/wiki/Crab#cite_note-8http://en.wikipedia.org/wiki/Predatorhttp://en.wikipedia.org/wiki/Osteichthyeshttp://en.wikipedia.org/wiki/Gondwanahttp://en.wikipedia.org/wiki/Cretaceoushttp://en.wikipedia.org/wiki/Adaptive_radiationhttp://en.wikipedia.org/wiki/Crab#cite_note-7http://en.wikipedia.org/wiki/Carapacehttp://en.wikipedia.org/wiki/Carboniferoushttp://en.wikipedia.org/wiki/Crab#cite_note-6http://en.wikipedia.org/wiki/Jurassichttp://en.wikipedia.org/wiki/Fossilhttp://en.wikipedia.org/wiki/Crab#cite_note-5http://en.wikipedia.org/wiki/New_Worldhttp://en.wikipedia.org/wiki/Old_Worldhttp://en.wikipedia.org/wiki/Lineage_(evolution)http://en.wikipedia.org/wiki/Monophyletic_grouphttp://en.wikipedia.org/wiki/Subtropicshttp://en.wikipedia.org/wiki/Crab#cite_note-4http://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Crab#cite_note-3http://en.wikipedia.org/wiki/Japanese_spider_crabhttp://en.wikipedia.org/wiki/Japanese_spider_crabhttp://en.wikipedia.org/wiki/Japanese_spider_crabhttp://en.wikipedia.org/wiki/Pea_crabhttp://en.wikipedia.org/wiki/Tropicalhttp://en.wikipedia.org/wiki/Land_crabhttp://en.wikipedia.org/wiki/Freshwaterhttp://en.wikipedia.org/wiki/Freshwaterhttp://en.wikipedia.org/wiki/Freshwaterhttp://en.wikipedia.org/wiki/Clawhttp://en.wikipedia.org/wiki/Exoskeletonhttp://en.wikipedia.org/wiki/South_Americahttp://en.wikipedia.org/wiki/Central_Americahttp://en.wikipedia.org/wiki/Land_crabhttp://en.wikipedia.org/wiki/Halloween_crab


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The larvae float in the pelagic zone of the ocean with other plankton for three to four

weeks,[5]

during which a large number of them are eaten by predators. The larvae pass

through three to five zoea stages before moulting into the post-larval glaucothoe stage;

this process takes from 25 to 33 days.[25]

Upon reaching the glaucothoe stage of

development, they settle to the bottom, find and wear a suitably sized gastropod shell,

and migrate to the shoreline with other terrestrial hermit crabs.[26]

At that time, theysometimes visit dry land. Afterwards, they leave the ocean permanently and lose the

ability to breathe in water. As with all hermit crabs, they change their shells as they

grow. Young coconut crabs that cannot find a seashell of the right size often use broken

coconut pieces. When they outgrow their shells, they develop a hardened abdomen.

The coconut crab reaches sexual maturity around five years after hatching.[22]

They

reach their maximum size only after 40 to 60 years.[10]

Measurement Of The Crabs:-

Stone Crab Measurement

Stone Crab claws must measure at least 2 3/4-inches in length measured by a straight

line from the elbow to the tip of the lower immovable finger. The forearm (propodus)

shall be deemed to be the largest section of the claw assembly that has both a

moveable and immovable finger and is located farthest from the body of the crab.

Spiny Lobster Measurement
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Spiny Lobster must have a minimum carapace length of greater than 3-inches and the

measurement must take place in the water. The carapace is measured beginning at the

forward edge between the rostral horns, excluding and soft tissue, and proceeding

along the middle to the rear edge of the carapace.

Colors and markings

Reproduction and development:

Hermit crab species range in size and shape, from species with a carapace only a few

millimetres long toCoenobita brevimanus, which can approach the size of a coconut.

The shell-less hermit crabBirgus latro(coconut crab) is the world's largest terrestrial

invertebrate.[10]

The young develop in stages, with the first two (the nauplius and protozoea) occurring

inside the egg. Most hermit crab larvae hatch at the third stage, the zoea. This is a larval

stage wherein the crab has several long spines, a long narrow abdomen, and large

fringed antennae. After several zoeal moults, this is followed by the final larval stage,

the megalopa stage.[11]

Reproduction

For marine creatures the most important way to distribute offspring to suitable newsites is by casting their fertilised eggs or juveniles adrift as plankton into water currents.

Most intertidal female animals produce hundreds, if not thousands, of eggs. Most will

not survive into adulthood, but are an excellent food supply for some other kind of

animal.

A planktonic development pattern is common in mostcnidaria,echinoderms,molluscs,

barnacles,decapod crabsandascidians.
http://en.wikipedia.org/wiki/Carapacehttp://en.wikipedia.org/wiki/Coenobita_brevimanushttp://en.wikipedia.org/wiki/Coenobita_brevimanushttp://en.wikipedia.org/wiki/Coenobita_brevimanushttp://en.wikipedia.org/wiki/Birgus_latrohttp://en.wikipedia.org/wiki/Birgus_latrohttp://en.wikipedia.org/wiki/Birgus_latrohttp://en.wikipedia.org/wiki/Invertebratehttp://en.wikipedia.org/wiki/Hermit_crab#cite_note-9http://en.wikipedia.org/wiki/Hermit_crab#cite_note-9http://en.wikipedia.org/wiki/Hermit_crab#cite_note-9http://en.wikipedia.org/wiki/Nauplius_(larva)http://en.wikipedia.org/w/index.php?title=Protozoea&action=edit&redlink=1http://en.wikipedia.org/wiki/Zoeahttp://en.wikipedia.org/wiki/Megalopahttp://en.wikipedia.org/wiki/Hermit_crab#cite_note-10http://en.wikipedia.org/wiki/Hermit_crab#cite_note-10http://en.wikipedia.org/wiki/Hermit_crab#cite_note-10http://www.mesa.edu.au/friends/seashores/cnidaria.htmlhttp://www.mesa.edu.au/friends/seashores/cnidaria.htmlhttp://www.mesa.edu.au/friends/seashores/cnidaria.htmlhttp://www.mesa.edu.au/friends/seashores/echinoderms.htmlhttp://www.mesa.edu.au/friends/seashores/echinoderms.htmlhttp://www.mesa.edu.au/friends/seashores/echinoderms.htmlhttp://www.mesa.edu.au/friends/seashores/molluscs.htmlhttp://www.mesa.edu.au/friends/seashores/molluscs.htmlhttp://www.mesa.edu.au/friends/seashores/molluscs.htmlhttp://www.mesa.edu.au/friends/seashores/barnacles.htmlhttp://www.mesa.edu.au/friends/seashores/barnacles.htmlhttp://www.mesa.edu.au/friends/seashores/decapods.htmlhttp://www.mesa.edu.au/friends/seashores/decapods.htmlhttp://www.mesa.edu.au/friends/seashores/decapods.htmlhttp://www.mesa.edu.au/friends/seashores/chordates.htmlhttp://www.mesa.edu.au/friends/seashores/chordates.htmlhttp://www.mesa.edu.au/friends/seashores/chordates.htmlhttp://www.mesa.edu.au/friends/seashores/chordates.htmlhttp://www.mesa.edu.au/friends/seashores/decapods.htmlhttp://www.mesa.edu.au/friends/seashores/barnacles.htmlhttp://www.mesa.edu.au/friends/seashores/molluscs.htmlhttp://www.mesa.edu.au/friends/seashores/echinoderms.htmlhttp://www.mesa.edu.au/friends/seashores/cnidaria.htmlhttp://en.wikipedia.org/wiki/Hermit_crab#cite_note-10http://en.wikipedia.org/wiki/Megalopahttp://en.wikipedia.org/wiki/Zoeahttp://en.wikipedia.org/w/index.php?title=Protozoea&action=edit&redlink=1http://en.wikipedia.org/wiki/Nauplius_(larva)http://en.wikipedia.org/wiki/Hermit_crab#cite_note-9http://en.wikipedia.org/wiki/Invertebratehttp://en.wikipedia.org/wiki/Birgus_latrohttp://en.wikipedia.org/wiki/Coenobita_brevimanushttp://en.wikipedia.org/wiki/Carapace


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The important issue is whether the currents will return the plankton to a suitable site for

juveniles to settle and grow to become reproductively mature adults.

Birth And Development:-

Size of pond and Pond constructionCrab fattening is carried out in ponds, cages or pens. Small tidal ponds ranging from0.025 to 0.1 ha in size with a water depth of 0.5-1.0 m are generally used for the

purpose. The pond should preferably have a sandy bottom to discourage burrowing.

Bunds should have a minimum width of 1.0 m at the top to prevent crabs from escaping

by burrowing through the bunds. Crabs are capable of climbing over the bunds, which

can be prevented by fixing overhanging fences on dykes. Fencing a height between 0.5

to 1.0 m over the dyke is done with materials like bamboo sticks, bamboo poles and

knotless nets, asbestos sheets, fibreglass panels, etc. As the crabs are highly

cannibalistic on the freshly moulted animals, 'hide outs'made out of hollow bamboo

pieces, cement pipes or stones are required to be placed inside the pond to minimise

mortality.Biological features

Mud crabs grow to a very large size of about 22 cm in carapace length and about 2 kg in

weight. The crabs belonging to the species S tranquebarica is free swimming and grows

to a large size with carapace width of 22 cm and those of species S. serrata have

burrowing habit and grow to about 14.7 cm in carapace width. Mud crabs are

omnivorous and they feed on a wide variety of food items and other crustaceans such as

shrimps& small crabs, bivalve molluscs and fish.

The females reach sexual maturity at a size of about 12 cm in S. tranquebarica and 8.5

cm in S.serrata in the brackish water regime. Both the species are continuous breederswith peak breeding seasons varying from place to place. The peak seasons of seed

abundance is May to October along the southwest coast, December to May in Tamil

Nadu coast and March to June in Chilka Lake. Each crab spawns once in two months.

The number of eggs carried by S. tranquebarica are about 1.1 to 7.0 million and by S.

serrata are 0.5 to 0.9 million. The berried females migrate from estuarine areas to the

inshore sea. The eggs hatch out in the sea and undergo metamorphosis later they

migrate to brackish water areas and spread to different parts of the estuarine systems.

Mating & Birthing

Crabs are born into litters, ranging from anywhere of a litter of 200-5,000. A mother

crab will normally go into heat two times a year: in-between cooking and cleaning

(which is sometime in June) and during football season.

After mating, the female will lay her fertilized eggs in the belly of the father, just like

seahorses, only gayer; this is considered the equivalent of "full custody" in the human

world. After having the young in his gut for about seven months, the father will give
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birth out of his anus. After being released from the dank, hairy tomb of their father's

ass, the young set out to start lives of their own.

Structure & Physiology

A typical crab. Note the yellow testicles, often mistaken for a limb by retards or those

who aren't doctors.

Crabs typically have six legs; five of those legs are used to move the crab, while the sixth

is actually mistaken for the crab's genitalia. In irony, crabs can catch a form of crabs as

well. These type of crabs are known as David Hasselhoffs.

Crabs have an excellent sense of smell. An average crab can smell a rather vile crotch

from three miles away, and a rather clean crotch only one mile away. However, a crab's

ability to smell frumunda cheese[4]

is proportional to it's size, or more accurately, it's

weight. It can be simply expressed by the following equation:

w(1.5) = s

In the equation above, wrepresents the crab's weight, where s roughly represents the

crab's range of smell in miles. Of course, because there's no way to measure the stench

of one's wang, it just can't be added into the formula. To change the above from grams

to ounces and/or miles to kilometers, use the following equation:

w(0.0352739619)(1.5) = s(1.609344)
http://uncyclopedia.wikia.com/wiki/Anushttp://uncyclopedia.wikia.com/wiki/Asshttp://uncyclopedia.wikia.com/wiki/Retardhttp://uncyclopedia.wikia.com/wiki/Doctorhttp://uncyclopedia.wikia.com/wiki/David_Hasselhoffhttp://uncyclopedia.wikia.com/wiki/Crab#cite_note-3http://uncyclopedia.wikia.com/wiki/Crab#cite_note-3http://uncyclopedia.wikia.com/wiki/Crab#cite_note-3http://uncyclopedia.wikia.com/wiki/Dickhttp://uncyclopedia.wikia.com/wiki/Dickhttp://uncyclopedia.wikia.com/wiki/Crab#cite_note-3http://uncyclopedia.wikia.com/wiki/David_Hasselhoffhttp://uncyclopedia.wikia.com/wiki/Doctorhttp://uncyclopedia.wikia.com/wiki/Retardhttp://uncyclopedia.wikia.com/wiki/Asshttp://uncyclopedia.wikia.com/wiki/Anus


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Now, an average crab weighs about two grams (a little more than one-hundredth of an

ounce), and based upon the above equations, can smell approximately three miles

(about 4.83 kilometers). For more reference, see the table below:

Weight (grams) Smell Distance (miles)

2 grams 3 miles

3 grams 4.5 miles

4 grams 6 miles

5 grams 7.5 miles


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Diet

Some crabs are scavengers and eat dead animals. Some eat

plankton. Some young crabs eat worms. Larger crabs eat

shrimp and other shellfish.

Size From 1 centimeter to nearly 2 meters

Color

Lined Shore crab - reddish-

purple

Kelp crab- brown on top,

reddish below

Purple Shore crab - dark

purple with purple spots on

claws

Hermit crab - gray-green

Lumpy crab - red-brown

Rock crab - light purplish-

red

Life CycleCrab eggs hatch into zoea larva which turn into megalopa

larva and then into crabs.

Predators fish, birds, octopus, and sea otters

Neat

Facts

A barnacle sometimes gets inside a male crab and takes

nourishment from its blood and changes its sex hormones,

so the next time it loses its shell it is a female.

TypesLined Shore crab, Spider crab, Kelp crab, Lumpy crab, Pea

crabs, Fiddler crab,

Relatives ghost shrimp (relative of the Hermit crab)
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Although crabs come in a variety of shapes and sizes they all have the same

general body plan. All crabs have one pair ofchelipeds and four pairs ofwalking legs. Also

referred to as claws, nippers or pincers, the chelipeds are the first pair of legs on a crab andtheir most distinguishing structure. Chelipeds are used for holding and carrying food, digging,

cracking open shells and warning off would be attackers. The carapace is the hard cover or

exoskeleton which protects the internal organs of the head, thorax and gills.

Visible on the underside of a crab are the mouthparts and the abdomen. The gills through

which the animal obtains oxygen cannot be seen. They are soft structures under the side of the

carapace. The eyes which protrude from the front of the carapace are on the ends of short

stalks. The mouthparts are a series of pairs of short legs, specialised to manipulate and chew

food.

The abdomen is small and tightly held against the underside of the body. Like all crustaceans

the sexes are separate and the size of the abdomen distinguishes them: in males it is triangular

and inset into the underside. In females it is broad and round and most obvious when the eggs

are being carried.


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Antenna- (pl. antennae) The long segmented appendages located behind the eyestalks. These

allow the crab to interact with its environment by touch and chemoreception.

Antennule- (pl. antennules) Shorter segmented appendages located between and below the

eyestalks, sensory organs; these also use chemoreception to "smell" and "taste"

Appendages- Ten legs (five pairs) including a claw-bearing pair with spines used for feeding and

defense, followed by three pairs of sharply pointed walking legs, and a pair modified as flat

swimming paddles at the rear, swimming legs.

Apron- Abdomen of a crab, which is folded under the body; male's is narrow and long. A

mature female's is semicircular, like the dome of the capitol building.

Carapace- The shell covering the body. It provides protective covering. It is made of chitin and

covers cephalothorax of the crab.

Cheliped- The first pair of legs, carries the large claw which is used for defense and obtaining

food. Male's claws are blue tipped with red; female's are red.

Eyes- Visual organs mounted on the ends of eyestalks. The eyestalks contain cells that release

hormones that inhibit molting and the development of gonads.

Lateral spines- Paired points on the widest outside edges of the carapace.

Mouth- Opening to the digestive system, located between the antennae. The mouth contains

jaws that hold and push food into the esophagus.

Sponge- Egg masses. Numbers of eggs vary, some may contain as many as

8,000,000. They are attached to swimmerets.


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Swimmerets- (pleopods) Paired abdominal appendages under the apron of the female crab on

which the eggs are carried until they hatch.

Swimming Legs- The last paired abdominal appendages, flattened for swimming.

Walking legs- 3 pairs. Used for movement; crabs are capable of walking forward or diagonally,

but usually they walk sideways.

Gills- Place of respiration and filtration, consisting of many plume-like filaments arranged

around a central axis. There are eight gills on each side.

Heart- The pump of the circulatory system. It is broad in size and located in the lower centerpart of the body.

Hepatopancreas- Digestive gland. Large organ with several functions, including the secretion of

digestive enzymes and absorption of digested food. It fills most of the area around the stomach,

depending on its contents of food and water.

Intestine- Portion of the digestive system through which digested food passes.


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Stomach- The organ of the digestive system that breaks down swallowed particles of food. It is

lined with small hard plates and projections.

Testes- Part of the male reproductive system, located on top of the hepatopancreas on either

side of the stomach.

Ovaries- Female reproductive organs that produce eggs and leading to the oviducts where eggs

are released.

Cartilage- Encases muscles that aid in movement of the legs. The muscles are the edible portion

of the crab.

Reproduction:

Female crabs usually lay their eggs shortly after copulating but can also store sperm for many

months. The eggs are fertilized as they are laid by passing through the chamber holding the

sperm. Eggs are brooded in a mass attached to hair on the female's abdomen. The number of

eggs carried can be very large but depends on the size of the crab. Some species may carry tens

of thousands of eggs when fully grown. Once developed the egg hatches into a tiny larva called

a zoea. Release of the zoea is aided by the female wafting her abdomen to and fro. The crab

larvae spends its life swimming in the plankton moulting several times until it reaches a stage

ready to settle on the sea floor again.


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Sense Organs:

Crabs have compound eyes consisting of several thousand optical units. The eyes are on stalks

which can be lowered for protection into sockets on the carapace. Crabs appear to see very

well with some species detecting movement 20 or 30 metres away. Crabs can also hear and

produce a variety of sounds. In courtship some species attract the females attention by banging

their cheliped on the ground or vibrating their walking legs. Each species has its own unique

sound that can attract a female or intimidate a competing male. Crabs have bristles and hairs

which act as touch receptors. The bristles occur all over the body but are most frequently foundin clumps on the walking legs. These bristles signal contact with a hard surface simply by

bending, whilst other shorter hairs are sensitive to water currents. Crabs can find food using

chemical stimuli. The antennae have "smell detectors" which detect chemicals that stimulate a

search for food. When similar detectors on the legs contact food the cheliped quickly grasps the

object and passes it into the mouth. Crab mouthparts have further receptors which are

sensitive to particular chemicals. Crabs rely on a combination of these sense organs to find food

and mates and flee predators.


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How its walks :

A crab has evolved to move sideways in response to its environment. Its body is

relatively flat with eyes that face forwards on stalks. It lives in rock crevices and moves sideways

across the surfaces of coral, etc with its back against the rock face, therefore always facing

outwards to possible threats from predators, other crabs, etc. When danger appears it can

easily conceal itself in gaps between rocks for protection where necessary. I have seen crabs do

this on many occasions.

http://www.youtube.com/watch?v=9Bl945vIPX8&feature=related

How it eat :

Crabs eat by catching or tearing food with their pincher claws and putting thefood into their mouths to digest it. A Crab has a claw to tear food and a claw to hold onto food.

Crabs are omnivorous in nature, that means they can eat plants and animals. Algae is the main

source of food for crabs. There are some crabs that can be scavengers and eat dead animals.

Coral crabs eat coral polyps found in the warm waters of the tropical oceans. The Ghost crabs

and Fiddler crabs eat mud and sand on the beaches. Pebble crabs and box crabs use their claws

as tools to crack open marine snails. It pulls the soft body of the snail and holds it in its mouth

and tears it apart to eat it.

http://www.youtube.com/watch?v=NN_Zyos6Ib0

The other things that crabs eat are:


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Marine crabs breathe underwater using gills, which are located in a two cavities under

the carapace. True land crabs have enlarged, modified cavities that act like lungs so that the

land crabs can breathe air.

How it attacks :

Crab attaks with their cheliped.

http://www.youtube.com/watch?v=DWcQ1pNn3sA

Influence of the bones on the muscle when movement takes place :

The crab and lobster are both crustaceans, who are invertebrates(animals without a spine). They have exoskeletons, which means their skeletal systems

are on the outside of the body with the muscle inside.

Composition :

Exoskeletons for crabs and lobsters are made of chitin, a semi-rigid protein

structure. Some species of crab (the hard-shelled varieties) also have calcium carbonate

embedded in the chitin, making it heavier and more rigid.

Muscle Attachment :

Exoskeletal systems for crabs and lobsters have several attachment points on

the inside for muscle. When you eat a crab's legs or a lobster's tail, you're eating the muscle

inside the skeleton. The nodules inside the shell are where the muscle attaches, holding the

meat in place.

Moulting :

When a crab or lobster grows, it sheds its exoskeleton. Moulting involves some risk

for the animal as it spends a few days waiting for the new shell to harden.


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Exoskeletons and Sensory Organs :

Crabs have tympani (eardrum-like organs for sensing sounds in water), which are

made out of a thinner layer of the same material as the exoskeleton. Lobsters have antennae

that are made of stalks of exoskeleton material and serve as vibration sensors like the tympani.

In addition to the vibration senses, lobster antennae have the smell and taste organs at their

ends. In both cases, the exoskeleton serves as more than armor for the body of the crustacean.

Segmentation and Movement :

Exoskeletons are usually divided into segments; the segment containing the

brain and the internal organs is usually more heavily protected. Segments in the body provide

attachment points for the legs, and the legs themselves are segmented so that they can move,

much the same way a knight's armor is segmented so that the knee joint can bend.


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CRAB MODELING AND TEXTURING

We started by taking the pictures of our character crab,i brought it from outside, and takenthe pictures. We shot some videos for reference.Then as a modeler i needed some more

images showing each and every part of crab in detail.So i collected as many references i

could from internet for eyes,mouth,legs and body.Then to know the shapes properly,i

collected images of skeleton.


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For the model sheet i used images as reference for getting front and profile views of crab...

Then for body and legs, i used one picture as an image plane for proportions to be

maintained properly.This pic was scaled to 3cm in maya as the average size of crab is

width: 11.6cm and height is 6cm and the cheliped size was 5cm.

I used this image from body modelling. The front and side views of the crab modelsheet.


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MODELING

I started with eye,probably and the upper body part of a model but the most

attractive part too......... And i was doing the

individuals parts of the eye and upper body part


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Then i moved on to the upper part of the body of crab.....


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Then i moved on to model the whole part of the body.....


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As modeling the part was done.....i started making the whole in the down part of the

body for the legs part of the crab....


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Then i completed making the wholes in the down part of the crab.....


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I have completed making the legs part. There are four legs with four different sizes and

shapes of the legs...


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Then i started to model the cheliped of the crab by using nurbs modeling and then

converted to polygon.....


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Now i completed the body, and i have made the mouth part of the crab..

Now i started modelling foot part....


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Now all the legs part is done.....

And then finally i merged the face and the body atlast. Before moving model to

unwarp...


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Wireframe of the model.... Front

Wireframe of the model.... Side


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Wireframe of the model.... Top

Now the model was almost done........

Now i exported the model as .obj....then for unwraping the model i used Headus uv

Layout,where i imported the .obj file and unwrappd the model.I used

2 uv sets for body and face and transferred the attributes to maya model...


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This is the uv layout in Maya...


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TEXTURING

Now the model was ready with uv s unwrapped.then i went through the basic

checklist and sent it for rigging and skinning. As the rigging part was started, i started the

texturing part.Initially i broke up the body into 2 parts body and legs,based on the 2 uv sets and

exported each of them as .obj. I used Mudbox for texturing.Now i started preparing stencils for

each and every part of the body taking diferent reference images.

After the stencils were done i started sculpting the head....


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After the Head was done i started sculpting the body part....

After the body was done i started sculpting the legs part...


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After painting of the body was done, i moved on to the Legs........


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So finally the coloring was done with sculpting...........


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EXTRACTING TEXTURE MAPS

After the texturing was done,the Normal map,Diffuse map,Displacement map,and the

VectorDisplacement maps are extracted from mudbox.

Example:Diffuse map of Body and Legs.


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Then after all the maps are extracted,i imported them into maya using the shading network

where all the maps are connected to their respective shaders.so now the model was finallyready with all the textures and was ready for lighting.


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RIGGING OF CRAB

Before starting the rig I referred to the real skeleton structure of the crab. But crab dosent have

skeleton system. and the way the crab walks,run,stands and stuff. I did skeleton on my own for

the crab to get movements which animator needs.

BASIC SKELETON :


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RIG WITH Ik HANDLES :

After i did basic skeleton i did ikHandles.

ADDED CONTRILS TO Ik HANDLES :

I have added both fk and ik controls and gave ik_fk_switch so that it would be easy for the

animator to switch from ik to fk whenever needed.


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FINAL CRAB RIG WITH CONTROLS:

SKIN:


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FINAL SKINNED CRAB:

After completing the rigging i have given for animation.


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Crab Animation

Crabs come in a variety of shapes and sizes they all have the same general body plan. All crabs

have one pair ofchelipeds and four pairs ofwalking legs.

I have taken the pictures and videos for reference for the movements of the legs

Then i have done observation on the leg movement by frame by frame key frame animation.

Then i have observe on the walk cycle, Each seperate leg of the crab.

I made the rough storyboard for the crab and there are 5 shots in the scene.

Story board of Crab (rough)


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Shot_01 :

After getting the tracking videos, i have analyse the videos. I have done 2d animation of

shot_01 for the sake of timing. Then i have analyse shot_01 and i have started doing animation

in maya.

Corrections:

In the 1st

shot no problem and corrections were occured.


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Shot_03 :



in maya.

Corrections:

In the 3rd shot, according to the camera movement the crab animation was not matching, so i

have done the keyframes animation of the crab after some frames.


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Shot_04 :



in maya.

Corrections:

In the 4th shot, i got no problem in this shot.


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Shot_05 :



in maya.

Corrections:

In the 5th shot, i got no problem in this shot.

These were all the 5 shots frm the scene.

After completing the animation for all the 5 shots. I have given these for VFX department.


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Match move

Artist:vijay prathap

The footage was taken with free camera so it had so many shakes and jerks.It was an interlaced

footage

It took so many days to track we had to do object track for shot no 5 and geometry track was

enough for the rest of the shots . Then these shots were exported to Maya Ascii 4.5 ,using the

track points we built the surounding rocks and ground which was not even and checker map

was applied .the tracked maya file was forwarded to the animators for placement of the

character.

In shot 5 we imported the plane in PF track to achieve the track even though it was not thatmuch perfect so we had to correct it by key frame animation .


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Lighting

Artist:Ragatej

The lighting for these shots were very typical firstly I used SIBL which was not at all suitable we

had a problem with the gamma values so we shifted to IBL .

Mostly I used spot lights and in some cases I also used area lights to match the character to the

scene.

Finally rendered in diferent passes such as Color,indirect,specular,light,fresnel,shadow and

occlusion.


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And composited in fusion :


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In compositing we had took the following indirect, light, AO and master beauty for body

contact passes . reflectivity, Fresnel and specular for light passes .Shadow and occlusion for

ground contact passes. We had to use master beauty instead of color because the texture was

not applied to the eyes in color pass and also the depth was missing .We did rotoscopy to make

the feel as the crab is coming outside of the hole in the footage.


crab dissertation

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