The Diversity of Life

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The Diversity of Life I. An Overview
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The Diversity of Life I. An Overview A.
Classifying Organisms
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The Diversity of Life I. An Overview A.
Classifying Organisms Initially, using a
Platonic, typological concept, Linnaeus and
others created a nested, hierarchical system.
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The Diversity of Life I. An Overview A.
Classifying Organisms Initially, using a
Platonic, typological concept, Linnaeus and
others created a nested, hierarchical
system. Evolution explained this nested pattern
as a consequence of descent from common
ancestors.
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The Diversity of Life I. An Overview A.
Classifying Organisms Initially, using a
Platonic, typological concept, Linnaeus and
others created a nested, hierarchical
system. Evolution explained this nested pattern
as a consequence of descent from common
ancestors. Modern biologists view the
classification system as a means of showing the
phylogenetic relationships among groups.
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The Diversity of Life I. An Overview A.
Classifying Organisms Initially, using a
Platonic, typological concept, Linnaeus and
others created a nested, hierarchical
system. Evolution explained this nested pattern
as a consequence of descent from common
ancestors. Modern biologists view the
classification system as a means of showing the
phylogenetic relationships among groups. Genetic
relatedness should be the basic for biological
classification...
Genus Felis
Genus Panthera
Family Felidae
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The Diversity of Life I. An Overview A.
Classifying Organisms B. Kingdoms
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The Diversity of Life I. An Overview A.
Classifying Organisms B. Kingdoms
Phylogenetic analysis revealed that the "Monera"
were an incredibly diverse group genetically.
Also, one subgroup - the Archea, were more
similar to Eukaryotes than to the other group of
prokaryotes (the 'Eubacteria').
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The Diversity of Life I. An Overview A.
Classifying Organisms B. Kingdoms
The most common way of ordering the major groups
of life has been the 5 kingdom approach.
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The Diversity of Life I. An Overview A.
Classifying Organisms B. Kingdoms
Phylogenetic analysis revealed that the "Monera"
were an incredibly diverse group genetically.
Also, one subgroup - the Archea, were more
similar to Eukaryotes than to the other group of
prokaryotes (the 'Eubacteria'). This required a
new way of looking at the most fundamental
groupings of life - and the introduction of a new
term Domains
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The Diversity of Life I. An Overview A.
Classifying B. Kingdoms C. Domains
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The Diversity of Life I. An Overview A.
Classifying B. Kingdoms C. Domains
Curiously, the very root of life may be invisible
to genetic analysis. Bacteria transfer genes by
division (to 'offspring'), but they also transfer
genes "laterally" to other living bacteria. This
makes reconstructing bacterial phylogenies
difficult.
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The Diversity of Life I. An Overview A.
Classifying B. Kingdoms C. Domains
Also, early evolution involved bacterial
symbioses and gene sharing between hosts and
symbionts
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The Diversity of Life I. An Overview A.
Classifying B. Kingdoms C. Domains
So, reconstructing the patterns of relatedness
among these ancient life forms is difficult.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
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The Diversity of Life II. An Overview of the
Bacteria
5 million to present
2.3-2.0 bya Oxygen
1.8 bya first eukaryote
0.9 bya first animals
0.5 bya Cambrian
0.24 byaMesozoic
0.065 byaCenozoic
4.5 bya Earth Forms
4.0 bya Oldest Rocks
3.4 bya Oldest Fossils
for 1/2 of life's history, life was exclusively
bacterial.... what were they doing? Spheres,
rods, and spirals were all they could come up
with?? Let's look...
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of organisms.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. A. Oxygen Demand all eukaryotes
require oxygen.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. A. Oxygen Demand all eukaryotes
require oxygen. bacteria show greater
variability - obligate anaerobes - die in
presence of O2 - aerotolerant - don't die,
but don't use O2 - facultative aerobes - can
use O2, but don't need it - obligate aerobes
- require O2 to live
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. A. Oxygen Demand all eukaryotes
require oxygen. bacteria show greater
variability - obligate anaerobes - die in
presence of O2 - aerotolerant - don't die,
but don't use O2 - facultative aerobes - can
use O2, but don't need it - obligate aerobes
- require O2 to live
represents an interesting continuum, perhaps
correlating with the production of O2 in the
atmosphere.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. B. Nutritional Categories
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. B. Nutritional Categories -
chemolithotrophs use inorganics (H2S, etc.) as
electron donors for electron transport chains and
use energy to fix carbon dioxide. Only done by
bacteria.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. B. Nutritional Categories -
chemolithotrophs use inorganics (H2S, etc.) as
electron donors for electron transport chains and
use energy to fix carbon dioxide. Only done by
bacteria. - photoheterotrophs use light as
source of energy, but harvest organics from
environment. Only done by bacteria.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. B. Nutritional Categories -
chemolithotrophs use inorganics (H2S, etc.) as
electron donors for electron transport chains and
use energy to fix carbon dioxide. Only done by
bacteria. - photoheterotrophs use light as
source of energy, but harvest organics from
environment. Only done by bacteria. -
photoautotrophs use light as source of energy,
and use this energy to fix carbon dioxide.
bacteria and some eukaryotes.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. B. Nutritional Categories -
chemolithotrophs use inorganics (H2S, etc.) as
electron donors for electron transport chains and
use energy to fix carbon dioxide. Only done by
bacteria. - photoheterotrophs use light as
source of energy, but harvest organics from
environment. Only done by bacteria. -
photoautotrophs use light as source of energy,
and use this energy to fix carbon dioxide.
bacteria and some eukaryotes. -
chemoheterotrophs get energy and carbon from
organics they consume. bacteria and some
eukaryotes.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. C. Their Ecological Importance
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. C. Their Ecological Importance -
major photosynthetic contributors (with protists
and plants)
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. C. Their Ecological Importance -
major photosynthetic contributors (with protists
and plants) - the only organisms that fix
nitrogen into biologically useful forms that can
be absorbed by plants.
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. C. Their Ecological Importance -
major photosynthetic contributors (with protists
and plants) - the only organisms that fix
nitrogen into biologically useful forms (that can
be absorbed by plants). Why is Nitrogen
important? - primary decomposers (with fungi)
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The Diversity of Life I. An Overview II. An
Overview of 'The Bacteria'
The key thing about bacteria is their metabolic
diversity. Although they didn't radiate much
morphologically (spheres, rod, spirals), they DID
radiate metabolically. As a group, they are the
most metabolically diverse group of
organisms. C. Their Ecological Importance -
major photosynthetic contributors (with protists
and plants) - the only organisms that fix
nitrogen into biologically useful forms that can
be absorbed by plants. - primary decomposers
(with fungi) - pathogens (cause disease)
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The Diversity of Life III. Domain Eukarya
Protists are single celled or colonial organisms
they are the most primitive eukaryotes, and they
probably evolved by endosymbiotic interactions
among different types of bacteria
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The Diversity of Life III. Domain Eukarya
From different types of protists evolved
different types of multicellular eukaryotes the
fungi, plants, and animals.
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The Diversity of Life III. Domain Eukarya
D. Diversity - green alga
Same chlorophyll as plants alternation of
generation genetic analysis confirms relatedness
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The Diversity of Life IV. Domain Eukarya
D. Diversity - Choanoflagellates
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II. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce)
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce)
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce) 2. Colonization of Land Environmental
Diffs Aquatic Habitats Terrestrial Water
available Desiccating
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce) 2. Colonization of Land Environmental
Diffs Aquatic Habitats Terrestrial Water
available Desiccating Sunlight
absorbed Sunlight available
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce) 2. Colonization of Land Environmental
Diffs Aquatic Habitats Terrestrial Water
available Desiccating Sunlight
absorbed Sunlight available Nutrients at
Depth Nutrients available
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce) 2. Colonization of Land Environmental
Diffs Aquatic Habitats Terrestrial Water
available Desiccating Sunlight
absorbed Sunlight available Nutrients at
Depth Nutrients available Buoyant Less
Supportive
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IV. Introduction to Plants A. Evolutionary
History 1. Green Algal roots Ulva (sea
lettuce) 2. Colonization of Land Environmental
Diffs Aquatic Habitats Terrestrial Water
available Desiccating Sunlight
absorbed Sunlight available Nutrients at
Depth Nutrients available Buoyant Less
Supportive Low oxygen, higher CO2 reverse
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IV. Introduction to Plants A. Evolutionary
History B. Adaptations to Life on Land C.
Plant Evolution Acquisition of Terrestriality
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V. Plant Diversity A. Non-Vascular (no true
xylem or phloem) 2. Example Mosses
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V. Plant Diversity B. Non-seed
Tracheophytes 1. Lycophytes (Club Mosses)
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III. Plant Diversity B. Non-seed
Tracheophytes 1. Lycophytes - (Club Mosses) -
ancient dominated first forests 300-350
mya
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III. Plant Diversity B. Non-seed
Tracheophytes 2. Ferns and their allies
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III. Plant Diversity B. Non-seed
Tracheophytes 2. Ferns and their allies -
true complex leaves - true roots - also
ancient appearing 350 mya - dominant
sporophyte reduced gametophyte
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Fern Life Cycle
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III. Plant Diversity C. Seed Tracheophytes 1.
Gymnosperms naked seed a. Evolutionary
History - dominated during Permian (280
mya) and through Mesozoic, and still
dominate in dry env. Today (high latitudes,
sandy soils)
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• Gymnosperm Life Cycle

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III. Plant Diversity C. Seed Tracheophytes 2.
Angiosperms flowering plants - flowers -
bribe pollinators - fruits - bribe seed
dispersers
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