today: our first presentations! macroevolution diversity! onto prokaryotes meeting the protists...
TRANSCRIPT
Today: Today:
• Our First Presentations!• Macroevolution
Diversity!• Onto Prokaryotes• Meeting the Protists• Overview of Fungi?
Thinking About MacroevolutionThinking About Macroevolution
What’s a
species??
Defining a Species: Defining a Species: the Biological Species Conceptthe Biological Species Concept
Defines a species as…Defines a species as…
a population (s) whose a population (s) whose members can members can potentiallypotentially interbreed in nature to interbreed in nature to produce viable, fertile produce viable, fertile offspring, but who offspring, but who can’tcan’t produce viable, fertile produce viable, fertile offspring with members of offspring with members of other speciesother species
??
Barriers leading to Biological Barriers leading to Biological Species:Species:
Barriers can Barriers can bebe
PREZYGOTIPREZYGOTI
CC
or or
POSTZYGOTIPOSTZYGOTICC
You Try: Part 1
How New How New Species Species
Can FormCan Form
Examples?
Next: Studying the Resulting Next: Studying the Resulting Diversity of Life!Diversity of Life!
Taxonomy and the ProkaryotesTaxonomy and the Prokaryotes
Photo: Pete Owens
A Bit of Taxonomy…A Bit of Taxonomy…
Studying Diversity: Studying Diversity: TaxonomyTaxonomy
Domain (Eukarya)Domain (Eukarya)
Kingdom (Animalia) Kingdom (Animalia)
Phylum (Chordata)Phylum (Chordata)
Class (Mammalia)Class (Mammalia)
Order (Primata)Order (Primata)
Genus (Genus (HomoHomo))
Species (Species (sapienssapiens))
Looking at Looking at the the
ProkaryotesProkaryotes
Where Did the First Life Come From?Where Did the First Life Come From?
Spontaneous Generation??
Biogenesis?
Photo: NIH
Step 1: Abiotic Step 1: Abiotic Synthesis of Organic Synthesis of Organic MonomersMonomers
Hey look! I’ve got amino
acids, sugars, lipids and
nucleotides in here!!
Where Did the First Life Come From?Where Did the First Life Come From?
Step 2: Abiotic Step 2: Abiotic Synthesis of Polymers Synthesis of Polymers (like proteins and (like proteins and nucleic acids)nucleic acids)
Binding to clay particles may have helped
facilitate this in the absence of enzymes!
Where Did the First Life Come From?Where Did the First Life Come From?
Step 3: Origin of Self-Replication MoleculesStep 3: Origin of Self-Replication Molecules
Where Did the First Life Come From?Where Did the First Life Come From?
Step 4: Formation of Pre-Cells (Protobionts)Step 4: Formation of Pre-Cells (Protobionts)
Where Did the First Life Come From?Where Did the First Life Come From?
What Did the First Life Look What Did the First Life Look Like?Like?
Prokaryotes show up Prokaryotes show up in the fossil record in the fossil record ~3.5 billion years ~3.5 billion years ago!ago!
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
They’re ubiquitous!They’re ubiquitous!
How do we know that if they’re so small?!?
You try: Part 2
Bacteria in a dental plague
Bacteria on the surface of a contact lens.
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Two Major Groups:Two Major Groups:
1.1. BacteriaBacteria
2.2. ArchaeaArchaea
(“Extremophiles”)(“Extremophiles”)
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Three Major Three Major Shapes/MorphologiesShapes/Morphologies::
1.1. CocciCocci
2.2. BacilliBacilli
3.3. SpirochetesSpirochetes
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Nutritionally Diverse! May be:Nutritionally Diverse! May be:
1.1. PhotoautotrophicPhotoautotrophic
2.2. ChemoautotrophicChemoautotrophic
3.3. PhotoheterotrophicPhotoheterotrophic
4.4. ChemoheterotrophicChemoheterotrophic
All of these terms describe how you get your energy (chemical
or light source) and where you get your carbon compounds
(make them yourself, or eat others!)
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Important as Disease Important as Disease Causing Agents!Causing Agents!
Many cause disease Many cause disease through the through the production of production of endotoxinsendotoxins or or exotoxinsexotoxins
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Important as Nutrient Cyclers!Important as Nutrient Cyclers!
Prokaryotes Today: Major Prokaryotes Today: Major CharacteristicsCharacteristics
Next Up: Evolution of the Next Up: Evolution of the Protistans!Protistans!
What the heck is a Protist?!?
Evolution Evolution of the of the
ProtistansProtistans
Diversity of the ProtistansDiversity of the Protistans1. The Protozoans – animal like protists Single-celled, animal-like eukaryotesSingle-celled, animal-like eukaryotes
Free-living and parasitic in moist environmentsFree-living and parasitic in moist environments Can reproduce sexually or asexuallyCan reproduce sexually or asexually Some famous Protozoans: Some famous Protozoans: GiardiaGiardia and and TyrpanosomaTyrpanosoma
Giardia lamblia trophozoites, as they appear with the scanning electron microscope. Original image by Arturo Gonzalez, CINVESTAV, Mexico.
2. The Slime Molds (Fungus-like Protists)
Diversity of the ProtistansDiversity of the Protistans
3. The Unicellular Algae
Most are Most are components of components of phytoplankton phytoplankton (basis of food (basis of food webs; global webs; global carbon sink!)carbon sink!)
Diversity of the ProtistansDiversity of the Protistans
Famous Single-Celled Algae: Red Tide, Famous Single-Celled Algae: Red Tide, PfiesteriaPfiesteria
The Protistans: The Single-Celled The Protistans: The Single-Celled AlgaeAlgae
Source: www.redtide.whoi.edu; www.pfeisteria.org
Diversity of the ProtistansDiversity of the Protistans
4. The Multicellular Algae
Three major Three major groups:groups:
1.1. Red AlgaeRed Algae
2.2. Brown AlgaeBrown Algae
3.3. Green AlgaeGreen Algae
You Try: Part 3
Next Up: Going Next Up: Going Multicellular and Heading Multicellular and Heading
for Land!for Land!
You Try: Part 4
Onto the Fungi: Onto the Fungi: Major Major
CharacteristicsCharacteristics
HETEROTROPHICHETEROTROPHIC
(use organic compounds for energy)(use organic compounds for energy)
Can be Can be SAPROBESSAPROBES (nutrients from (nutrients from nonliving organic matter) or nonliving organic matter) or
PARASITESPARASITES (extract nutrients from a (extract nutrients from a living host)living host)
EXTRACELLULAR DIGESTIONEXTRACELLULAR DIGESTION EUKARYOTICEUKARYOTIC
The Fungi: General LayoutThe Fungi: General Layout
The Fungi: General LayoutThe Fungi: General Layout
The Major The Major Fungi Fungi
GroupsGroups
The ZygomycetesThe Zygomycetes
Mycorrhizae
Pilobolus- decompose
s animal dung!
The Club Fungi The Club Fungi (Basidiomycetes)(Basidiomycetes)
Mushrooms, shelf fungi, puffballs and Mushrooms, shelf fungi, puffballs and rustsrusts
Important decomposers of wood and Important decomposers of wood and plant materialplant material
Plant Pathogens!Plant Pathogens!
Fairy Fairy RingsRings
WHY??WHY??
Lichens:Lichens:A Fungal A Fungal LifestyleLifestyle
Lichens: A Fungal LifestyleLichens: A Fungal Lifestyle
Other Amazing FungiOther Amazing Fungi
Mycorrhizae
Pilobolus-