1. Chapter 2
Evolution and Ecology

2. Evolution is the genetic adaptation of organisms to the environment.
Chapter Opener
Evolution is the genetic adaptation of
organisms to the environment.
Natural selection ---Charles
Darwin and Alfred Wallace 1858
operates through the following steps
Variation occurs in every group of plant and animal
Every population of organism produces an excess of offspring
Not all individuals will survive and reproduce
Only those individuals est able to obtain and use these resources will
survive and reproduce
5) The favored traits will be more frequent in the next generation

3. Bird predation is selection force Lichens die
Figure 2-1
Bird predation is selection force
Lichens die

4. Biston betularia f. typica, the white-bodied peppered moth.
Biston betularia f. carbonaria, the black-bodied peppered moth.

5. Three types of selection on phenotypic characters
Figure 2-2
Type type type 3
Three types of selection
on phenotypic characters

6. Grant 1986 : Princeton Univ. Directional selection
Figure 2-3
Grant 1986 : Princeton Univ. Directional selection
Severe draught: large beaks
Crack large seeds
Galapagos finch (from ): example of directional selection
Severe draught ---bird with larger beaks

7. example of Stabilizing selection: birth weight in human in the USA
Figure 2-4
Mean = 3.4 kg
4.2 kg- mortality lowest
Infant mortality
example of Stabilizing selection: birth weight in human in the USA

8. example of stabilizing selection, northern Canada
Figure 2-5
Snow geese:
example of stabilizing selection,
northern Canada
-”safety-in-numbers”
Predator: fox

9. Decoy
“Safety –in- numbers advantage

10. Both are from plankton feeding marine ancestor
Figure 2-6
1. Small Limnetic
(open water)
Both are from plankton feeding
marine ancestor
2. Larger Benthic
Example of disruptive selection

11. 실험 방법 서식처 패치 4등분 -선택 횟수 (%) -체류 시간 (%) -이동 방식 (안쪽,중앙,바깥) 포식자 투입 전·후
잔가시고기(Pungitius kaibarae)
short ninespine stickleback
IUCN, NT(준위협)종
서식처 패치 4등분
-선택 횟수 (%)
-체류 시간 (%)
-이동 방식 (안쪽,중앙,바깥)
포식자 투입 전·후
행동패턴의 변화 파악
옆에서 본 모습
돌무지
모래사장
빈 공간 수초
위에서 본 모습
: 개체 및 포식자 투입 위치

12. 파란색-포식자 X
붉은색-포식자 존재
포식자가 존재
수초 선택 상승
빈공간 선택 감소

13. Clutch size: penguin1 egg, pigeon 1or 2, gull-3, Canada goose 4-6
Figure 2-7
Clutch size: penguin1 egg, pigeon 1or 2, gull-3, Canada goose 4-6
American merganser 10
What determines clutch size?
-Proximate factors: physiological factors
-Ultimate factors: clutch size are requirement of long-term (evolutionary) survival.
Lack clutch size (Cost-benefit model)

14. Figure 2-8
Determinate layers: ex) pigeon—2 eggs
Intermediate layers: continue to lay egg
until the nest is full
Herring gull: 16 egg (normal clutch 2-3)
House sparrow: 50 egg (normal 3-5)
EXP.
Lack clutch size: 11
Individual birds appear to produce the clutch size that maximize their reproductive potential

15. ? Do not agree with the predictions from Lack’s hypo.
Figure 2-9
EXP. in Costa Rica
Vanderwaerf (1992):
Evaluation of 77 exp.
69 % -the most productive
clutch size was larger than
the most common clutch size
Highly energetic or delayed ?
Average: 3.5
(mean brood size three or four) - +
Do not agree with the predictions from Lack’s hypo.

16. Figure 2-10
skip
These results would predict directional selection for increased clutch size

17. Coevolution: together evolution Arms Races= predator prey
Figure 2-11
탁란: 뻐꾸기
Coevolution: together evolution
Arms Races= predator prey
cowbird

18. Newt: highly toxic to most animal (도롱뇽)
Figure 2-12
Examples of Arms Races
Newt: highly toxic to most animal (도롱뇽)
Garter snake consume Newt, have evolved
resistence to their toxins
Garter snake in
San Francisco population is 100 times more
resistant than Oregon population. Why?
Newt poison-geographical mosaic.
Arms race-- continue

19. Gamete selection (eg. Sperm mobility)
Figure 2-12
Selection
Gamete selection (eg. Sperm mobility)
Individual s.: Darwinian most common
Kin s.
Group s.
alarm of ground squirrel
Kin selection