evolution topic 5

Phylogeny

History of evolution of a species or a group of organisms derived from a common ancestor

6 kingdoms

Fungi, plantae, animalia, archaebacteria, protista, eubacteria

3 domaine

Archa, eukarya, bacteria

Evidence of changing earth (evolution)

Anatomy

Fossil records

Earths history (biogeography)

Eco chemistry

Relative dating

Method of determining the age of fossils/rocks based of DEPTH

Absolute dating

Method of determining the age of fossils/rocks based on DECAY

Geologic time scale

séries of major and minor divisions that correspond to major evolutionary events

Biogeography

Study ig geographic distribution of life on earth

Plate tectonics

Explains how earth changed from a single continent (pangera) into present continents

Homologous structures (anatomy)

Similar origin, different function

Analogous (anatomy)

Different origion, similar function

Embryonic development

Similarities between embryos of different species,

Many embryos structures are similar to those found in common ancestors

Vestigial features

rudimentary structures with no useful function

Ex. Wisdoms teeth

Biochemistry

Similar species have similar DNA, molecules, and proteins

DNA is composed of 4 nucleotides based

A

T

C

G

Aristotle

Theory of spontaneous generation

Belived species change over time and that living things emerge from non living matter

Buffon

Theory of fossil evidence

Said species could not change over time

Lamarck

Theory of inheritance of acquired characteristics

Organisms can produce new parts or get rid of unwanted parts

Charles Darwin

Theory of natural selection

Explains how species change of time through randome genetic mutations that could be passed on!

Malthus

Essay on populations

All species produce more offspring than are able to survive

Alfred Wallace

Same conclusions of natural selection as Darwin - population remains stable in size

-survival of the fittest

Darwin’s theory

1. Population stays stable in size

2. Overpopulation (Malthus)

3. Survival of the fittest (species compete for limited resources)

4.Variation (DNA mutations)

5. Survival of the fittest (natural selection)

6. Speciation

Variation (DNA mutations)

No two individuals are identitcal

Sexual reproduction=variation

Different traits occur in the offspring

These traits are passed on the next generation

Spéciation

New species arise by the accumulation of inherited variations over several generations

(Known as evolution)

Individuals do not change, populations do!

Once a population becomes so different, new species!

Sources of inherited variations (mutations)

Mutations are randome changes in DNA

Caused by:

Environmental factors, mitosis,

Mutations = diversity

Mutations can be GOOD and BAD

Ex. Cheetah has ability to run fast

Spéciation and evolution

Spéciation = formation of new species

3 step process of speciation:

1. Geographic isolation - a physical barrier separates a single interbreeding population

2. Unique mutations -mutations that occur in each new population are NOT shared

3. Reproduction isolation -the two populations eventually are so different that even if rétinites they would NOT mate

Darwin’s finches

They became different species of finch!

Why? They were geographically isolated from the mainland, leading to speciation

Rate of change in species (how populations evolve)

1. theory of gradualism

States that changes to species happen at a slow steady pace

2. Theory of punctuated equilibrium

   -proposed by Eldredge and Gould

   -states that: species evolve rapidly

   -speciation usually occurs in small, isolated populations

-intermediate fossils are rare

Why? After a burst of change, the species are well adapted to their environment and do not need to change for a long time