BIOL213 Chp25 - created from Mind Map

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What is fossil

strengths

Weaknesses

In what environment do they form

piece of physical evidence

from organisms lived in the past

FOSSIL RECORDS

used for studying the history of life

evolutionary history

PHYLOGENETIC TREE

What is Phylogenetic tree?

Formation

CLADISTIC APPROACH

Simplified diagram

describing organisms evolutionaly histories

studied by fossil records

powerful tool for studying the history of life

Why??

convenient to see the relationship between species

as well as evolutionary histories

Show evolutionary related ness

Study organisms

TYPES OF GROUPING ( EVOLUTIONARY UNITS)

This is divided by traits

(1) Monophyletic Group (clade)

(2) Polyphyletic Group

(3) Paraphyletic Group

COMPLICATION IN GROUPING

Divided by Synapomorphy of organisms

Sharing similar traits

They developed independently

Having the same traits in one large group, but not all species

Homology v.s. Homoplasy

How to group organisms??

Homology

Homoplasy

Organisms are similar due to common ancestory

Organisms having similar traits which they evolved independently

Homologous v.s. Convergent (Both are Homoplasy)

Homologous

Convergent

Having common ancestors at some point

Organisms living in similar environment

Making data set

There are so many possibilities

How to make a data?

Filtering methods

(1) Parsimony

(2) Evolutionary distance

(3) Maximum likelihood and Bayesian analysis

Data with less evolutionary changes are more likely

More rapid evolutionally changes are more likely

Research DNA sequences

Root

Node

Outgroup

Sistergroup

Branch

Tip

MISUNDERSTOOD!!

Traits

the most ancestral branch

the most recent common ancestor

show where do they split

groups that don't have the same traits

species or groups that are closely related

line representing the relatedness

Branch Lengths

(1) Show how species diverged

(2) Show when species extinct

each specie

(1) the nearest branch does not represent the closest specie

amount of nodes do not represent how many revolutions ocuured

trees can be drawn differently

Characteristics of species

TYPES OF TRAITS

Synapomorphy

Apomorphy

traits that found in two or more groups

present in most recent common ancestor

traits that developed individually

grouping method of species

based on phylogenetic trees

Clades

Groups of species = clades

Lineages

Fossil biases

Habitat Bias

Toxanomic & Tissue Bias

Temporal Bias

Abundance Bias

Organisms living in specific environment = more likely to fossilize

Organisms with hard body parts = more likely to fossilize

Organisms born recently = their fossils likely to be found

Organisms with larger population = their fossils likely to be found

(1) when they buried rapidly

(2) when they decompose slowly

Types of Fossils

Used to estimate The Life's Time Line

Intact fossil

Compression fossil

Cast fossil

Perminerized fossil

Trace Fossil

Organisms remain undamaged

sediment compress organisms

organisms decomposes

leaving just shapes of organisms

organisms decompose slowly

minerals turn organisms into stone

Organisms' footprint and tracks remain

LIFE'S TIME LINE

Hadean Eon

Major evolutionary events

Dominant Taxa

Mass extinction

4570 mya

Archaean Eon

Earth formation

Proterozoic Eon

First oceans

Phanerozoic Eon

First cynobacteria

Paleozoic era

Mesozoic era

Cenozoic era

First eukaryotic cells

First Photosynthetic Eukaryotic cells

EUKARYOTES

First multicellular organisms

BIOL213 Chp27

Origin of life

Photosynthetic cells

First oxygen formation

Cambrian Explosion: Diversification of animals

First arthropods, mollusks, vertebrates

Adaptive Radiation

Land plants

Bony fish, tetrapods, plants with seeds

origin of amniotes

First dinosaurs, mammals

Bird like reptile, angiosperm, bee, ant

First horses, rabbits

fully aquatic whales

chimpanzees

Single lineage rapidly produce many species

Why does this occur??

Cambrian explosion

Ecological opportunity

Innovations

Environmental change

Mutation favored by natual selection

More resources

Few competitions

Morphological

Physiological

Behavioral

Formation of reproductive structure that helped diversifying

Ability to live in new environments, ability to fly

Birds started dancing when they attract others to find mates

Diverse of animals, land plants, fungi

Plants: Gymnosperms Animals: Dinosaurs

Plants: Angiosperms Animals: Birds & Mammals

Ordovician Extinction

Extinctions

rapid extinction of large number of diverse species

Devonian Extinction

Permian extinction

Triassic Extinction

Caused by Flood basalts (volcanos)

acid rain > devastated plants and organisms

oceans lacked oxygen > sealevel dropped

Cretaceous Extinction

Asteroid impact

the largest tsunami

blocked the Sun for long periods

extensive acid rain

Background extinction

lower, natural, and average rate of extinction

normal environment change

competition to other species

Occur in extraordinary and sudden change in environment

4000 mya

3700 mya

3600 mya

3000 mya

2500 mya

541 mya

485

444

359

299

252

201

66

145

Present

1000 mya