Lec 1_Evol_web

Lec 1_Evol_web - Lecture 1: Evolution Intro & Evidence...

Info iconThis preview shows pages 1–20. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 1: Evolution – Intro & Evidence
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The process that has transformed life on Earth from its earliest forms to its current vast diversity. Evolution is THE CENTRAL & UNIFYING concept in biology! “Nothing in biology makes sense except in the light of evolution” – Theodosious Dobzhansky What is Evolution?
Background image of page 2
Theories of evolution can explain: 1. Transition from non-living to living forms 2. Adaptations of Organisms 4. Fossil Record (including human evolution) 5. Ecological Interactions 6. Practical Problems of Humans: a) Health b) Food Production c) Aggression
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Evolution occurs in populations , not individuals*. *all of the individuals that regularly interbreed (roughly defined as all the members of a species in a particular area). Gene Pool = all genes in population Properties of Evolution
Background image of page 4
1) Usually requires a lot of time*. Properties of Evolution *But not always!
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2) Evolution requires genetic variation to act on. - The variation originally comes from mutations. Properties of Evolution photo of snail shells Photos of: human faces human hands human ears
Background image of page 6
3) Requires inheritance of genetic information Joshua Elizabeth Jonathan Abigail jr. Hepzibah John Abigail dd dd dd dd dd dd Dd Dd Dd Dd Dd Dd Dd Dd Dd Dd Dd Dd DD DD D D DD DD Dd Dd Dd Dd DD DD Pedigree for some trait.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4) Evolution is not directed toward a predetermined goal. “Great moments in evolution” trajectory followed depends on natural selection genetic variation Wrong!
Background image of page 8
T t Imagine tadpole of a frog species in which tail length is determined genetically T allele dominant to t Does best in fast moving water & in deep water Does best in shallow water near shore of lakes A simple example of evolutionary change:
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Both forms present in this environment Photo of lake
Background image of page 10
T T T t T T T T T t t t t t t t T t t t T: 9 copies t : 11 copies In Average Lake Sample
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Imagine a change in conditions over a long time period. Short-tailed form doesn’t survive well. Photo of stream
Background image of page 12
T T T t T T T T T t t t t t t t T t t t T: 9 copies t : 11 copies
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
T T T t T T T T T t t t t t t t T t t t
Background image of page 14
T T T t T T T T T t t t T t t t T: 12 copies t : 8 copies T t T T
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
T T T t T T T T T t t t T t t t T t T T
Background image of page 16
T T T T T T T T T t t t T T T: 16 copies t : 4 copies T t T T T T
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
T T T T T T T T T t TT T T T: 19 copies t : 1 copies T T T T T T
Background image of page 18
T: 9, 12, 16, 19 t: 11, 8, 4, 1 Successive generations
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 20
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 72

Lec 1_Evol_web - Lecture 1: Evolution Intro & Evidence...

This preview shows document pages 1 - 20. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online