the benefits of healthy ecosystems

2008 Fall Lecture 5 SCIE 103 Life Sciences 1

The Benefits of Healthy Ecosystems Ecosystem services are the benefits people obtain from ecosystems. Many of

the services listed here are interlinked. Provisioning Services. These are the products obtained from ecosystems,

including: Food. This includes the vast range of food products derived from plants, animals, and

microbes. Fibre. Materials such as wood, jute, cotton, hemp, silk, and wool. Fuel. Wood and other biological materials serve as sources of energy. Genetic resources. This includes the genes and genetic information used for animal

and plant breeding and biotechnology. Biochemicals, natural medicines, and pharmaceuticals. Many medicines and food

additives such as alginates, and biological materials are derived from ecosystems. Ornamental resources. Animal and plant products, such as skins, shells and flowers

are used as ornaments and whole plants are used for landscaping and ornaments. Freshwater. Freshwater in rivers is also a source of energy. Because water is required

for other life to exist, it could also be considered a supporting service.


The Benefits of Healthy Ecosystems Regulating Services. These are the benefits obtained from the regulation of

ecosystem processes, including: Air quality regulation. Ecosystems both contribute chemicals to and extract

chemicals from the atmosphere, influencing many aspects of air quality; Climate regulation. Ecosystems influence climate both locally and globally. Changes

in land cover can affect both temperature and precipitation. Water regulation. The timing and amount of runoff, flooding, and aquifer recharge can

be strongly influenced by changes in land cover. Erosion regulation. Vegetation plays an important role in soil retention and the

prevention of landslides. Water purification and waste treatment. Ecosystems can help to filter out and

decompose organic wastes introduced into inland waters and coastal ecosystems. Disease regulation. Changes in ecosystems can directly change the abundance of

human disease. Pest regulation. Ecosystem changes affect the frequency of crop and livestock pests

and diseases. Pollination. Ecosystem changes affect the distribution, abundance, and effectiveness

of pollinators.


The Benefits of Healthy Ecosystems Cultural Services. These are the non-material benefits people obtain from

ecosystems through spiritual enrichment, reflection, recreation, and aesthetic experiences, including: Cultural diversity. The diversity of ecosystems is one factor influencing the diversity of

cultures. Spiritual and religious values. Many religions attach spiritual and religious values to

ecosystems or their components. Knowledge systems (traditional and formal). Ecosystems influence the types of

knowledge systems developed by different cultures. Educational values. Ecosystems and their components and processes provide the

basis for both formal and informal education in many societies. Inspiration. Ecosystems provide a rich source of inspiration for art, national symbols,

architecture, and advertising.Aesthetic values. Many people find beauty or aesthetic value in ecosystems, as reflected in the support for parks, scenic drives, and the selection of housing locations.

Social relations. Ecosystems influence the types of social relations that are established in particular cultures.

Sense of place. Many people value the "sense of place" that is associated with recognized features of their environment.

Cultural heritage values. Many societies place high value on the maintenance of either historically important landscapes ("cultural landscapes") or culturally significant species.

Recreation and ecotourism. People often choose where to spend their leisure time based in part on the characteristics of the natural or cultivated landscapes in a particular area.


The Benefits of Healthy Ecosystems Supporting Services. Supporting services are those that are

necessary for the production of all other ecosystem services. They differ from provisioning, regulating, and cultural services in that their impacts on people are often indirect or occur over a very long time. Soil Formation. Because many provisioning services depend on soil fertility,

the rate of soil formation influences human well-being in many ways. Photosynthesis. Photosynthesis produces oxygen necessary for most living

organisms. Primary Production. The assimilation or accumulation of energy and

nutrients by organisms. Nutrient cycling. Approximately 20 nutrients essential for life, including

nitrogen and phosphorus, cycle through ecosystems and are maintained at different concentrations in different parts of ecosystems.

Water cycling. Water cycles through ecosystems and is essential for living organisms.


Ecosystem Service Ecosystem Functions Examples

Gas regulation Regulation of atmospheric chemical composition

CO2/O2 balance, O3 for UVB protection, SOx levels.

Climate regulation Regulation of global temperature, precipitation and other climatic processes

Greenhouse gas regulation.

Disturbance regulation Storage, damping and other responses to environmental fluctuations

Storm protection, flood control, drought recovery and other habitat responses, mainly controlled by vegetation structure and landforms.

Water regulation Regulation of hydrological flows. Water for agriculture, industry, transportation or power generation.

Water supply Storage and retention of water Storage of water in watersheds, reservoirs and aquifers.

Erosion control and sediment retention

Retention of soil within an ecosystem.

Prevention of soil loss by wind, runoff or other processes, storage of silt in lakes and wetlands.

Soil formation Soil formation processes. Weathering of rock and the accumulation of organic material.

Nutrient cycling Storage, internal cycling, processing and acquisition of nutrients.

Nitrogen Fixation, N, P and other elemental or nutrient cycles.


Ecosystem Service Ecosystem Functions Examples

Waste treatment Recovery of nutrients and removal or breakdown of excess nutrients and compounds.

Waste treatment, pollution control, detoxification.

Pollination Fertilization of flowers. Providing pollinators for the reproduction of plant populations.

Biological control Population regulation. Predator control; reduction of herbivory.

Refugio Habitat for resident and transient populations.

Nurseries, migration habitat, over wintering grounds.

Food production Production useable as food. Fish, game, crops, nuts and fruits.

Raw materials Production useable as raw materials.

Lumber, fuel, fodder.

Genetic resources Sources of unique biological materials and products.

Medicine, products for materials science, resistant genes/strains, ornamental species.

Recreation Opportunities for recreational activities.

Eco-tourism, sport fishing, hunting, hiking, camping.

Cultural Non-commercial uses. Aesthetic, artistic, educational, spiritual, scientific.


Threats to biodiversity

In part because the value of biodiversity and the resulting ecosystem services are poorly understood by a lot of people, nature's “cogs and wheels” are going missing at an alarming rate — on the order of 100 to 1000 times the background rate, estimated from fossil records to be from one to ten species/year (Pimm, et al., 1995 and others). Some estimates of current rates are much higher. There have been five mass extinctions in the past 500 million years, the most recent about 65 million years ago (Raup and Sepkoski, 1982). We appear to be in the sixth, with the major difference being that for this one, the cause appears to be not a major physical catastrophe such as severe volcanism or a meteor strike, but a single species: us.

The Millennium Ecosystem Assessment (2005) reports that there has been a substantial and largely irreversible loss in the earth's biodiversity, with some 10-30% of mammal, bird and amphibian species currently threatened with extinction, and 15 of 24 ecosystem services being degraded. Fortunately, it comes at a time when the earth probably contains more species than ever before (Rhode and Muller, 2005), and there's some redundancy built into the system. We can lose some species — some — before things start to really unravel.


Threats to biodiversity

The causes of these losses are varied and can be encompassed in the term HIPPOC: Habitat loss: Habitat loss,

alteration and fragmentation directly affect the species that rely on the habitat that is being changed.


Threats to Biodiversity – Habitat Destruction Habitat destruction – single greatest threat to

biodiversity


Deforestation of tropical forests


Deforestation Closer to Home


Threats to Biodiversity – Habitat Destruction Fragmentation of a forest ecosystem


Threats to Biodiversity The history of habitat reduction and fragmentation in a Wisconsin

forest


Threats to Biodiversity – Habitat Destruction Tropical forests house between 50 and 90 percent of species live

on earth. About 17 million hectares of tropical forests – an area four times the size of Switzerland – are now being cleared annually, and scientists estimate that at these rates roughly 5 to 10 percent of tropical forest species may face extinction within the next 30 years.

Rates of tropic forest loss are accelerating, and some particularly species-rich forests are likely to be largely destroyed in our lifetime. Some scientists believe that about 60,000 of the world's 240,000 plant species, and perhaps even higher proportions of vertebrata and insect species, could lose their lease on life over the next three decades unless deforestation is slowed immediately.


Threats to Biodiversity – Habitat Destruction Tropical forests are by no means the only sites with endangered

biodiversity. Worldwide, nearly as much temperate rainforest – once covering an area nearly the size of Malaysia – has also been lost. Although the total extent of forest in the northern temperate and boreal regions has not changed much in recent years, in many areas the species-rich, old-growth forests have been steadily replaced by second-growth forests and plantations. Evidence of accelerating clearance of temperate forests is also appearing: between 1977 and 1987, 1.6 million hectares of forest was lost in the United States alone.

In several spots in Europe, fungal species diversity has dropped by 50 percent or more over the past 60 years. In such "Mediterranean" climates as California, South Africa, central Chile, and Southwest Australia, at least 10 percent of all plant and animal species are imperiled. The largest number of recent extinctions has been on oceanic islands: some 60 percent of plant species endemic to the Galapagos Islands are endangered, as are 42 percent of the Azores' endemic species and 75 percent of the endemic plant species of the Canary Islands.


Threats to biodiversity The causes of these losses are varied

and can be encompassed in the term HIPPO(C): Invasive (Introduced) species:

Invasive species are harmful non-native species whose introduction or spread threatens the environment, the economy and society, including human health. Invasive species originate from other continents, adjacent countries or from other ecosystems within Canada. Free from predation and competition that would normally limit their distribution and abundance in their natural habitats, many invasive species reproduce rapidly and damage, displace or destroy native species in our forests (e.g., emerald ash borer), agricultural areas (e.g., plum pox virus), wetlands (e.g., purple loosestrife) and lakes and rivers (e.g., zebra mussel). The zebra mussel disrupts ecosystem composition and structure, clogs water intake pipes, and affects public beaches.

emerald ash borer

plum pox virus zebra mussel


Threats to Biodiversity – Introduced Species Introduced Species

Ranking second to habitat loss as a cause of biodiversity crisis Species that humans move from the species’ native locations to

new geographic regions. Of all 1,880 imperiled species in the United States, 49% are

endangered because of introduced species alone or because of their impact combined with other forces.

Introduced species are a greater threat to native biodiversity than pollution, harvest, and disease combined.

Through damage to agriculture, forestry, fisheries, and other human enterprises, introduced species inflict an enormous economic cost, estimated at $137 billion per year to the U.S. economy alone.

Some introduced species (such as most of our food crops and pets) are beneficial. However, others are very damaging.


Threats to Biodiversity – Introduced Species The Asian chestnut blight fungus

virtually eliminated American chestnut from over 180 million acres of eastern United States forests in the first half of the 20th century. It was a disaster for many animals that were highly adapted to live in forests dominated by this tree species. For example, ten moth species that could live only on chestnut trees became extinct.

The Australian paperbark tree has replaced native plants, such as sawgrass, over 400,000 acres of south Florida, because it has a combination of traits (for example, spongy outer bark and flammable leaves and litter) that increase fire frequency and intensity. Many birds and mammals adapted to the native plant community declined in abundance as paperbark spread.


Threats to Biodiversity – Introduced Species Pump house and water control

structure for green-tree impoundment at Montezuma National Wildlife Refuge in central New York. Waterfowl broods produced in adjacent flooded forest found excellent foraging conditions among floating and emergent aquatic plants in the foreground, 18 June 1968.

Ten years later, purple loosestrife had displaced native food and cover plants in the waterway surrounding the green-tree impoundment at the Montezuma Refuge. Biologist holding stadia rod in middle foreground is obscured by mature plants. Note the abundance of Lythrum salicaria seedlings along the water line, 16 August 1978.


Threats to Biodiversity – Introduced Species Zebra mussels (Dreissena polymorpha) are

small, fingernail-sized mussels native to the Caspian Sea region of Asia. They are believed to have been transported to the Great Lakes via ballast water from a transoceanic vessel. The ballast water, taken on in a freshwater European port was subsequently discharged into Lake St. Clair, near Detroit, where the mussel was discovered in 1988. Since that time, they have spread rapidly to all of the Great Lakes and waterways in many states, as well as Ontario and Quebec. Diving ducks and freshwater drum eat zebra mussels, but will not significantly control them. Likely means of spread: Microscopic larvae may be carried in livewells or bilgewater. Adults can attach to boats or boating equipment that is in the water.


Threats to Biodiversity – Introduced Species Nile perch (Lates niloticus),

a voracious predator introduced to Lake Victoria as a food fish, has already extinguished over one hundred species of native cichlid fish there.

The introduction of Nile perch into Australia was considered after a reduction in Queensland barramundi stocks, but this was decided against due to the devestation they caused in several African lakes.


Threats to Biodiversity – Introduced Species A parasite can be

similarly devastating. The sea lamprey reached the Great Lakes through a series of canals and, in combination with overfishing, led to the extinction of three endemic fishes.


Threats to Biodiversity – Introduced Species Scientific name: Boiga irregularis Common name: Brown tree snake Native To: Australia Date of U.S. Introduction: First

detected in Guam in the 1950s, introduced in cargo from the Admiralty Islands.

Means of Introduction: Arrived in Guam accidentally in imported cargo

Impact: Preys on native lizards and birds, has eliminated ten of the eleven native bird species from the forests of Guam; causes frequent power outages by climbing on electrical wires

Current U.S. Distribution: Guam


Threats to Biodiversity – Introduced Species The first Argentine ants set foot on U.S. soils in

the late 1890's, as coffee ships from Brazil unloaded their cargo in New Orleans. Being prolific breeders and constantly on the go, they moved across the southern half of the United States. A single colony may contain 10,000 female workers, and there may be hundreds of colonies around your home; the total number of ants could easily reach a million. Although they cannot sting, they can bite; however, they are only about 3 mm long and there tiny mandibles are too small to hurt humans. But, in the world of insects, these ants are truly a living terror. They are very aggressive and readily overtake other ant species, even ants that are much larger and with powerful stings. Argentine ants are relentless and simply outnumber their adversaries until the enemy colony is destroyed. They even attack paper wasp nests under the eaves of a house, forcing the huge wasps to flee their nests in terror. Even nests of large carpenter bees are no match for these relentless ants. A "killer bee" nest probably could not withstand an invasion of Argentine ants. They also will attack bird nests, driving off the mother bird and killing the helpless young. One possible redeeming quality about these little warriors is that they may attack dry-wood (aerial) termite colonies in your home.


Threats to Biodiversity – Introduced Species Beauty can be a trap, and

despite the appeal of the Caulerpa taxifolia with its lovely green flowers, this invasive species represents a great danger for neritic Mediterranean habitats. These algae preferentially invade posidonia prairies, impoverishing the already threatened marine flora and fauna.

Caulerpa taxifolia

Posidonia


Threats to Biodiversity – Introduced SpeciesSome impacts of invaders are subtle but nonetheless

destructive to native species: North American gray squirrels are driving native red squirrels to

extinction in Great Britain and Italy by foraging for nuts more efficiently than the native species. Such competition for resources is not easy to observe, but the end result is the loss of a native species.

Hybridization, or cross-breeding, of introduced species with natives is an even subtler impact (no lineage goes extinct), but it is insidious because it leads gradually to the extinction of many native species, as their gene pools inevitably evolve to become those of the invader. Introduced mallards, for instance, are driving the native Hawaiian duck to a sort of genetic extinction by breeding with them.

Of 26 animal species that have gone extinct since being listed under the Endangered Species Act, at least three were wholly or partly lost because of hybridization with invaders. One was a fish native to Texas, eliminated by hybridization with introduced mosquito fish.


Threats to Biodiversity – Introduced Species Rainbow trout introduced widely in

the United States as game fish are hybridizing with five species listed under the Endangered Species Act, such as the Gila trout and Apache trout.

The endangered, endemic Hawaiian duck is being lost to hybridization with North American mallards introduced for hunting.

The rarest European duck (the white-headed duck) is threatened by hybridization with the North American ruddy duck, which was originally kept as an amenity in a British game park. The ruddy duck escaped, crossed the English Channel

white-headed duck

ruddy duck


Threats to Biodiversity – Introduced Species Often invaders interact with one another to generate a problem

where either species alone would be harmless. For example, ornamental fig trees in the Miami area for over a century stayed where planted, in people's yards, because they were sterile. Each fig species requires a particular wasp to pollinate it, and the wasps were absent. About fifteen years ago, the pollinating wasps for three fig species arrived independently in the region, and now these fig species are reproducing. At least one has become invasive, with seedlings and saplings being found many miles from any planted figs. More cases of this phenomenon, termed "invasion meltdown," are likely to arise as more species are introduced and have the opportunity to interact with each other.


Threats to biodiversity The causes of these losses are varied and can be encompassed in the term

HIPPO(C): Pollution: Pollution is emitted in many different forms, including atmospheric pollution, soil and

water pollution, pesticides, particulate matter, and heavy metals. There are thousands of pollutants circulating through the Earth's ecosystems, and many of these materials have significant, large-scale impacts on forests and aquatic ecosystems. Acid precipitation, for example, has had a significant impact on Ontario's maple forests and industrial pollutants such as DDT is known to have caused significant declines in populations of many bird species including Peregrine Falcon and Bald Eagles. Pollution can also disrupt ecological processes. For example, scientists are now linking light pollution to declines in migratory songbirds.

Population growth: Human population growth adds to the impact of all the other causes because more people require more space and more resources. There are now about 6 billion people on Earth, more than twice as many as in 1950. While the rate of increase is slowing, it still adds more than 90 million people each year. Habitats, even healthy ones, can support just so many of anything, including people.

Over-consumption or unsustainable use: Over-consumption is the harvest of species at a rate higher than can be sustained by the natural reproduction of the population. In Ontario, for example, wild American ginseng has been over-harvested from its natural rich woodland habitat to the point of being Endangered.

Climate Change and other Cumulative impacts: People have added carbon dioxide, nitrous oxide, methane and other greenhouse gases to the atmosphere by extracting and burning fossil fuels such as coal, oil and natural gas. The effect of these gases has been to trap heat and accelerate the rate of global warming and climate change. Climate change is a major threat to the world's biodiversity. The cumulative impacts of pollution, habitat modification, the global redistribution of species and over-harvesting place many ecosystems at risk. These cumulative impacts cause alteration, reduction and loss of ecosystem function, populations and species, degradation, loss and fragmentation of habitat. They also damage human health.


Threats to Biodiversity - Overconsumption

Refers generally to the human harvesting of wild plants and animals at rates exceeding the ability of the populations of those species to regenerate.

Logging, hunting and fishing Especially susceptible are large species with

low intrinsic reproductive rates. Eg. Elephants, whales, rhinoceroses, and

species on small islands.


Threats to Biodiversity - Overconsumption A new global study concludes that

90 percent of all large fishes have disappeared from the world's oceans in the past half century, the devastating result of industrial fishing.

The study, which took 10 years to complete and was published in the international journal Nature, paints a grim picture of the Earth's current populations of such species as sharks, swordfish, tuna and marlin.

The authors used data going back 47 years from nine oceanic and four continental shelf systems, ranging from the tropics to the Antarctic. Whether off the coast of Newfoundland, Canada, or in the Gulf of Thailand, the findings were dire, according to the authors.


Reducing the threats to biodiversity The global response to HIPPOC has been the promotion of sustainable

development, defined by the OBS as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.”

But what does that mean, in a practical sense? One way is to link biodiversity to sustainable development through the concept of “sustainable use: the use of components of biodiversity in a way and at a rate that does not lead to their long-term decline, thereby maintaining the potential for future generations to meet their needs and aspirations” (OBS, 2005). We don't want to lose species because it will eventually degrade our natural capital, and any reduction in ecological services is a sure sign that biodiversity is eroding.

The loss of a single species is not “the end of the world as we know it,” but cumulatively it may be. Losing species destabilizes ecosystems and weakens their ability to deal with natural disasters such as floods, droughts and fire and with human-caused stresses such as pollution and climate change. The precautionary principle states, when in doubt do no harm. In this case, stopping all species loss where possible is probably the best rule of thumb.

Blue-Ringed Dancer (Argia sedula)


What can you do to help? Learn more. Knowledge is power. The more we know about the causes, consequences

and how to prevention of biodiversity loss, the more power we will have to act. Also, our actions will be more efficient and focused.

Tell others. As we learn more about biodiversity, we need to let others know as well that biodiversity conservation is worth pursuing. We can discuss it among groups we belong to. We can write letters or emails to editors and others of influence.

Help monitor biodiversity. Citizen science, the monitoring of species and ecosystems by individuals and groups, is growing across the world. It's a good way to involve people who already have an interest and perhaps knowledge of nature. Learn more and make a difference!

Get organized. Work is ongoing on many of the Action Items. If you belong to organizations that should be involved, contact that group, encourage involvement and offer to help.

Reduce our Ecological Footprints. We all do things every day which directly or indirectly affect biodiversity by putting pressure on our natural systems. Reduce such pressure by: Being aware of Species at Risk and taking action to protect their populations or habitat. Being knowledgeable of Invasive Species, and acting to limit their spread. Creating habitat for wild things on your property - planting butterfly or wildflower gardens with

native plants and trees, maintaining brush piles, or participating in a local habitat restoration project.

Avoiding pesticides, herbicides and chemical fertilizers. Buying locally grown food whenever possible. Reducing energy use in homes, businesses and institutions and vehicles.

Influence politicians. Let politicians at all levels know that biodiversity conservation is a critical issue that the government needs to do more about.


What is a "Species at Risk?"

A species at risk is any native plant or animal that is at risk of extinction or of disappearing from its natural environment.

“Endangered species” – one that is in danger of extinction throughout all or a significant portion of its range.

“Threatened species” – those that are likely to become endangered in the foreseeable future throughout all or a significant portion of their range.

http://www.iucnredlist.org/info/tables/table5

Region Mammals Birds Reptiles Amphibians Fishes Mollusks Other Inverts Plants Total

Turkey 18 15 13 9 54 0 12 3 124


Threats to Biodiversity The Great Auk is an extinct flightless bird that has become a symbol of

destruction of the Earth and its life forms. The last authenticated sighting of this species was from Fire Island off the coast of Cape Reykjanes, Iceland, on June 3, 1844. At that time a pair of adult Great Auks were caught and killed by collectors. The adults had laid an egg and were incubating. That was probably the last egg ever laid of this species. Great Auk specimens soon came to rest in major collections and museums in Europe and North America. This was largely due to bequests of private collections, integration of collections into one facility and purchases of collections from estates. One of Canada's few specimens, at the Royal Ontario Museum, arrived there from such a purchase.


Threats to Biodiversity Greater mouse-eared

bat (Myotis myotis) The greater mouse-eared bat

is one of the larger European bats and has become extinct in England. Its fur is a medium-brown colour on the upper body, and greyish-white underneath. It has large ears with a very prominent tragus, the organ which is part of the bat’s echolocation system.

Status: Classified as Extinct in the UK. Listed under Appendix II of the Bonn Convention, Annex II of the Berne Convention, Annex II & IV of the EC Habitats Directive and Schedule 5 of the Wildlife and Countryside Act (as amended).


A hundred beats from extinction: Most Endangered Species of 2007 The western lowland gorilla (Gorilla

gorilla gorilla) is one of many new additions to the World Conservation Union (IUCN)'s 2007 Red List of Threatened Species, which was made public today. Since 2006, the annual assessment of the planet's imperiled wildlife has grown by more than a thousand species and now totals 41,415.

Many great apes end up on the list, as their habitat is continually under threat from human activities.

Western lowland gorilla populations in central Africa have collapsed due to the commercial bush meat trade and the Ebola virus. And in Indonesia, orangutans are critically endangered because of forest logging and clearing land for palm oil plantations. (National Geographic Sept. 12, 2007)


A hundred beats from extinction: Most Endangered Species of 2007 The baiji (Lipotes vexillifer), or Chinese

river dolphin— deemed "functionally extinct" by a team of scientists in December—was downgraded from "endangered" to "critically endangered (possibly extinct)" on the IUCN's 2007 Red List.

Populations of the light blue-gray animal, which lives in China's polluted Yangtze River, have plummeted over the last 30 years.

A possible sighting in August 2007 is currently being investigated by Chinese scientists, but even if one or two dolphins are found, the baiji is almost certainly doomed.

“Freshwater dolphins are very vulnerable, because rivers tend to be heavily used by humans and there is nowhere else for the dolphins to go,” Caroline Pollock, a Red List program officer, told National Geographic News.


A hundred beats from extinction: Most Endangered Species of 2007 The Egyptian vulture, a new

addition to IUCN's 2007 Red List, has declined along with many other vulture species. Five species of vulture, including the Egyptian, have been reclassified to a higher threat level since 2006. Asian vultures have declined rapidly over the last eight years due to the use of a livestock drug called diclofenac.

African vultures are struggling due to habitat loss, a lack of food, and collisions with power lines.

The scavengers are also being killed by insecticide-laden carcasses, which have been deliberately baited to poison livestock predators such as hyenas.


A hundred beats from extinction: Most Endangered Species of 2007 Mexico’s Santa Catalina Island

rattlesnake has been classified as critically endangered on the 2007 IUCN Red List. The snake, found on just one island, sports highly desirable patterned skin that has made it a collector's item for hunters.

New reptile surveys are revealing the fragile nature of many reptile populations.

For instance, a major survey of North American reptiles has bumped up the region's Red List reptile species to a total of 738.

The main culprit behind their decline is habitat loss due to expanding cities, Caroline Pollock, a Red List program officer, told National Geographic News.

“Unlike birds and mammals, we haven't assessed all the reptiles on the planet,” Pollock added.


A hundred beats from extinction: Most Endangered Species of 2007 The Banggai cardinal fish's popularity as

a pet for the home aquarium has landed it on the 2007 IUCN Red List. In the wild, the striped fish is only found in the Banggai Archipelago off Indonesia.

Human pressures such as the aquarium trade are the main reason for the fish's decline, with habitat loss and climate change also posing major threats.

Fish stocks are in free-fall all over the world, both from overfishing and the aquarium trade. Scientists estimate current extinction rates are at least a hundred to a thousand times higher than natural rates.

“We need to protect the world's biodiversity in order to ensure a sustainable future for all of us,” Caroline Pollock, a Red List program officer, told National Geographic News.


A hundred beats from extinction: Most Endangered Species of 2007 Reptiles such as the gharial

are becoming more prominent on the IUCN's Red List each year. Despite its fearsome appearance and lengths of up to 19 feet (6 meters), the Indian gharial is not a man-eater and prefers to eat fish.

Its long, thin snout, which makes it easily distinguishable from a crocodile, also allows it to quickly capture fish.

Habitat loss and poaching is driving the animal toward extinction.


A hundred beats from extinction: Most Endangered Species of 2007 For the first time, corals were added to

the 2007 Red List. A recent scientific survey on the Galápagos Archipelago has added ten corals to the list, including the Floreana coral.

In the 1980s, frequent El Niño weather patterns—which made ocean temperatures fluctuate—likely led to the poor state of the Galápagos corals.

Some scientists worry that global warming may make El Niño events more regular and prevent corals from recovering.

Until recently, scientists had not properly assessed the health of the world's tropical corals. Scientists estimate that human activities—such as pollution, global warming, and sedimentation—could kill 30 percent of reefs in the next three decades.

Coral reefs in the Indian and Pacific Ocean, for example, are vanishing faster than rain forests.


A hundred beats from extinction: Most Endangered Species of 2006 Polar bears and hippos for the first

time join more than 16,000 species threatened with extinction, according to the World Conservation Union.

The Switzerland-based nonprofit, known as IUCN, released its 2006 Red List of Threatened Species on May 2. The list shows a significant increase in the number of species on the brink since the last list was released in 2004.

The Red List now marks polar bears as vulnerable, largely because of habitat loss linked to global warming. Due to decreasing sea ice in the Arctic, "polar bears are predicted to suffer more than a 30% population decline in the next 45 years," the group wrote in a press release.

The following images highlight other Red List species, from pink pigeons to blue poison frogs.


A hundred beats from extinction: Most Endangered Species of 2006 Manta rays, familiar

denizens of tropical and subtropical ocean-shelf waters, are classified as near threatened on the 2006 IUCN Red List. Of the 547 shark and ray species assessed, the group says, 20 percent are in danger of extinction.


A hundred beats from extinction: Most Endangered Species of 2006 Native to the Indian Ocean

island of Mauritius, the pink pigeon has been suffering from decades of habitat loss and introduction of invasive predators. The population dropped to a mere 12 known birds by 1986, according to the nonprofit Mauritian Wildlife Foundation. The bird is now listed as endangered on the IUCN Red List.


A hundred beats from extinction: Most Endangered Species of 2006 In addition to land and

marine animals, the IUCN Red List includes a number of plants and fungi, such as the Italian funcia di basiliscu. This fungus, which grows on the island of Sicily, is listed as critically endangered.


A hundred beats from extinction: Most Endangered Species of 2006 Amphibian populations in

Central and South America have been declining rapidly, a trend that many experts link to environmental factors. The blue poison frog of Suriname, which grows up to one and three quarters of an inch (four and a half centimeters) long, is given "vulnerable" status on the 2006 IUCN Red List.


A hundred beats from extinction Factors leading to

mammals' extinction continue with "ever increasing intensity"

Siberian tigers may vanish within three decades.


A hundred beats from extinction Lion populations have fallen by

almost 90% in the past 20 years, leaving the animal close to extinction in Africa. There are now only 23,000 left, compared to an estimated 200,000 two decades ago.

The problem will get worse as Kenya's human population doubled in the next 12 years.

The wild dog population has fallen to between 3,500 and 5,000 and there are now fewer than 15,000 cheetahs.


A hundred beats from extinction Orangutans once ranged

throughout Southeast Asia. Today they can be found only on the Indonesian islands of Borneo and Sumatra. Scientists estimate that in the last 10 years their numbers have been reduced by up to 50 percent, to perhaps as few as 13,000 living in the wild.


A hundred beats from extinction Mutisia magnifica: An Ecuadorian

species threatened by charcoal production

The species most at risk live only in small geographic ranges in specific habitats.

The official estimate by the World Conservation Union - the IUCN - suggests that 13% of the world's plant species are under threat, but the two US botanists say it is at least 22% and could be as many as 47%.

They say the IUCN has reliable data for plants in Europe, North America, South Africa and Australia, but there are no reliable figures for tropical, developing countries, where most of the world's plants grow.

Passiflora loxensis

Mutisia magnifica


Threats to Biodiversity The dramatic losses of species and ecosystems obscure equally large

and important threats to genetic diversity. Worldwide, some 492 genetically distinct populations of tree species (including some full species) are endangered. In the northwestern United States, 159 genetically distinct populations of ocean-migrating fish are at high or moderate risk of extinction, if they have not already slipped into oblivion.

Loss of genetic diversity could imperil agriculture. How much the genetic base has already eroded is hard to say, but since the 1950s, the spread of modern "Green Revolution" varieties of corn, wheat, rice, and other crops has rapidly squeezed out native landraces. Modern varieties were adopted on 40 percent of Asia's rice farms within 15 years of their release, and in the Philippines, Indonesia, and some other countries, more than 80 percent of all farmers now plant the new varieties. In Indonesia, 1500 local rice varieties have become extinct in the last 15 years. A recent survey of sites in Kenya with wild coffee relatives found that the coffee plants in two of the sites had disappeared, three sites were highly threatened, and six were possibly threatened. Only two were secure.


Threats to Biodiversity The impact of losses of genetic

diversity often registers swiftly. In 1991, the genetic similarity of Brazil's orange trees opened the way for the worst outbreak of citrus canker recorded in the country. In 1970, U.S. farmers lost $1 billion to a disease that swept through uniformly susceptible corn varieties.

Similarly, the Irish potato famine in 1846, the loss of a large portion of the Soviet wheat crop in 1972, and the citrus canker outbreak in Florida in 1984 all stemmed from reductions in genetic diversity. In such countries as Bangladesh, where some 62 percent of rice varieties come from a single maternal plant, Indonesia (74 percent), and Sri Lanka (75 percent), such outbreaks could occur at anytime.


Threats to Biodiversity

The loss of genetic, species, and ecosystem diversity both stems from and invites the loss of cultural diversity. Diverse cultures have bred and sustained numerous varieties of crops, livestock, and habitats. By the same token, the loss of certain crops, the replacement of traditional crops with export crops, the extinction of species embedded in religion, mythology, or folklore, and the degradation or conversion of homelands are cultural as well as biological losses. Since 1900, experts say, about one Indian tribe has disappeared from Brazil each year. Almost one half of the world's 6000 languages may die out in the next 100 years. Of the 3000 languages expected to survive for a century, nearly half will probably not last much longer.

Ubık ( Ubykh): Northwestern Caucasian Language. Last spoken person Tevfik Esenç died on October 1992.

http://encyclopedia.thefreedictionary.com/Dead+language


Tevfik Esenç Tevfik Esenç (1904 – October 7, 1992) was a Circassian exile in

Turkey and the last known speaker of the Ubykh language. Esenç was raised by his Ubykh-speaking grandparents for a time in the village of Hacı Osman köyü in Turkey, and he served a term as the muhtar (mayor) of that village, before receiving a post in the civil service of Istanbul. There, he was able to do a great deal of work with the French linguist Georges Dumézil to help record his language. Blessed with an excellent memory, and understanding quickly the goals of Dumézil and the other linguists who came to visit him, he was the primary source of not only the Ubykh language, but also of the mythology, culture and customs of the Ubykh people. He spoke not only Ubykh but Turkish and the Hakuchi dialect of Adyghe, allowing some comparative work to be done between the two languages. He was a purist, and his idiolect of Ubykh is considered by some as the closest thing to a standard "literary" Ubykh language that existed. Esenç died in 1992 at the age of 88. The inscription that he wanted on his gravestone read as follows:

This is the grave of Tevfik Esenç. He was the last person able to speak the language they called Ubykh.


Gaining Biodiversity

Mutation Mutations increase genetic diversity by altering the genetic material (almost always DNA) of organisms. Once mutations arise, they are passed on to the mutated organism's offspring, and in time may either disappear if the line dies out. Depending upon the specific mutation, the result can range from no effect whatsoever to the creation of an entirely new species. Although this gives rise to differences in organisms, it is an extremely slow process compared to the other ways in which local diversity increases. Ultimately, though, this is the only way in which diversity is truly created.


Gaining Biodiversity Speciation

The creation of a new species is known as speciation. Species are typically defined as a group of related organisms that share a more or less distinctive form and are capable of interbreeding and producing fertile offsprings. The origin of new species naturally has the largest immediate effect on species-level diversity; the immediate changes to genetic and ecosystem diversity are usually minimal, though the effects will grow in time. Speciation can occur through several different means, including geographical isolation, competition, and polyploidy. Geographical Isolation: Geographical isolation, such as new

mountain chains or a lake whose level lowers enough that it splits into two separate lakes, can divide a population into two separate populations. The two isolated populations continue to evolve separately from one another. Eventually they can diverge to a great enough degree, either through adaptation to their differing environments or through random mutations, that they are no longer able to interbreed and are considered to be different species.


Gaining Biodiversity Speciation

Competition: If a new resource, such as a new food source, becomes available to a population, some part of the population may become specialized in obtaining that resource. Being specialized in obtaining either the new resource or the original resource may be better than trying to obtain both. If so, then the specialists would be better off mating with the other specialists on the same resource, as mating with someone who uses the other resources will result in offspring that aren't specialized for either resource and at a disadvantage. In time, there is a chance that the population will split into two species, each specialized on one of the two resources. This can happen, but it is probably a fairly rare event.

Polyploidy: Speciation through polyploidy happens far more often in plants than in animals, as animals are much more sensitive to large changes in their genetic structure. Most species are diploid, meaning they have two copies of each chromosome (large packages of DNA), one from each of their parents. An individual in a normally diploid species may have more copies of these chromosomes, being polyploid ("poly" meaning many), through errors at the cellular level. The additional copies of the chromosomes render them unable to produce functional offspring with normal members of their species. Plants often fertilize themselves to at least some extent, so polyploid species can arise from a single individual. This method of speciation is almost instantaneous, happening in a single generation, and is more common in plants than animals.


Galapagos Finches


Gaining Biodiversity

Immigration Immigration increases diversity as new individuals and perhaps

even new species enter an area, increasing its diversity. The rate at which immigration happens depends on the size of the area in question, how many species are there already, and how close the area in question is to the source of immigration. Even if a species is unable to survive in an area, a constant flow of immigrants to the area can keep the species present indefinitely. Island biogeography is the classic theory on the topic of how these factors affect immigration and more, and is explained above.

Most species that immigrate to a new ecosystem have only minor effects on their new system, though some drastically change it. Zebra mussels, native to the Caspian Sea and Ural river, were first recognized in the Great Lakes in 1988. It is most likely that they were brought over in ballast water. Since then they have spread throughout the Great Lakes and beyond, killing native mussel populations and fouling all manner of pipes and intakes.


Gaining Biodiversity Succession

Succession is the process through which an area gains species as successive communities of organisms replace one another until an endpoint is reached. This endpoint, or climax community, is commonly a forest. Succession may begin on bare rock, an abandoned field, the burned remnants of a forest, or any stage before the endpoint. A hypothetical bare field isn't bare for long before annual plants appear. They are replaced within a few years by perennial plants and shrubs, who in turn are replaced by pine trees. Eventually, hardwood trees invade and replace the pines, forming the hardwood climax community.Different regions have varying climax communities. One usually refers to the different stages of succession in terms of the plants rather than the animals because the plants precede the animals and provide the structure and environment that the animals live in. One exception to this is aquatic communities, where sponges, corals, bivalves and other animals are responsible for much of the three-dimensional structure of the community.The climax community is typically the most diverse stage of succession, and each stage of succession is more diverse than the one preceding it. This pattern depends on the group being looked at; plant diversity actually decreases at the final stage, while animal diversity increases to the end. Species that were common in the early stages of succession will not be common in the later stages, but may still be found if small disturbances in the area effectively set the disturbed area back to an earlier successional stage.


Does Diversity lead to Stability? Although it is a key question, the relationship between diversity and stability is still being resolved. As with many topics in biodiversity, there are different ways of expressing stability. One way is to define it as the ability of a system to return to its original state after being disturbed, so how quickly it can return and how large a disturbance it can return from are key variables. Another definition is how resistant to change the system is in the first place. No matter what the definition used, however, there are definite trends that appear.

Current consensus is that greater diversity does lead to greater stability, for three general reasons: Insurance Effect: Different species do better under different conditions. As the number of species increases, the

range of conditions that at least some species do well in also increases. When perturbations do occur, it's more likely that some of the species present will be able to do well, and these species will protect the community as a whole.

Averaging Effect: Stability is measured as variability relative to community abundance. As diversity increases, the value of the variability will naturally decrease. One problem with this is that the impact of additional species can be confused with the effect of larger numbers of individuals (see Doak et al. 1998 and Tilman et al. 1998 for examples of this debate).

Negative Covariance Effect: Since species are competing for resources such as space and food, any gains that one species makes will be to some extent at the expense of the other. This means that as a species does more poorly its competitors will do better. The result is that disturbances aren't as detrimental to the entire system as they could be, as the losses in one species are offset by the gains of another.

The structure of a food web also affects the stability of the system. Food webs describe the flow of energy through the system, basically who eats whom and how often. Different levels exist, such as producers (usually plants), primary consumers (herbivores i.e. who eat plants), secondary consumers (who eat herbivores), and so on. The food web used to be called the food chain, but the amount of cross-links makes the whole thing more properly resemble a web than a simple linear chain.

Most of the links in the food web are weak, meaning that the consumer doesn't depend excessively on what it consumes. As long as the links are weak, no species will be greatly affected by a predator or prey whose population changes. Strong links means that species are greatly affected by changes in the populations of species they're linked to; if there are many strong links in the system, drastic changes in one species spread through the system along the strong links, destabilizing it.

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