Chapter 22: Descent with Modification: A Darwinian View of Life
Post on 24-Feb-2016
40 Views
Preview:
DESCRIPTION
Transcript
Chapter 22: Descent with Modification: A Darwinian View of Life
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?
- Gradual change over time3. What is paleontology?
- Study of fossils- Allows for relative dating – older or younger – layer found in
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?
- Inheritance of acquired characteristics- Evolution within an organism’s lifetime – use & disuse- Examples – Blacksmith, giraffe
5. What was Darwin’s view?- Descent with modification – tree of life- REPRODUCTION of the fittest - not SOTF- Story time…
EnglandEUROPE
NORTHAMERICA
GalápagosIslands
Darwin in 1840,after his return
SOUTHAMERICA
Cape ofGood Hope
Cape Horn
Tierra del Fuego
AFRICA HMS Beagle in port
AUSTRALIA
TasmaniaNewZealand
PACIFICOCEAN
And
esATLANTICOCEAN
Figure 22.5 The voyage of HMS Beagle
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?
- Inheritance of acquired characteristics- Evolution within an organism’s lifetime – use & disuse- Examples – Blacksmith, giraffe
5. What was Darwin’s view?- Descent with modification – tree of life- REPRODUCTION of the fittest - not SOTF- Story time…..- Studied Galapagos finches
Figure 22.6 Beak variation in Galápagos finches
(a) Cactus eater. The long,sharp beak of the cactusground finch (Geospizascandens) helps it tearand eat cactus flowersand pulp.
(c) Seed eater. The large groundfinch (Geospiza magnirostris)has a large beak adapted forcracking seeds that fall fromplants to the ground.
(b) Insect eater. The green warbler finch (Certhidea olivacea) uses itsnarrow, pointed beak to grasp insects.
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?
- Inheritance of acquired characteristics- Evolution within an organism’s lifetime – use & disuse- Examples – Blacksmith, giraffe
5. What was Darwin’s view?- Descent with modification – tree of life- REPRODUCTION of the fittest - not SOTF- Story time…..- Studied Galapagos finches- 1859 – The Origin of Species – 2 main points
- Descent with Modification (evolution) f/ common ancestor- Natural selection is the mechanism of evolution
Figure 22.7 Descent with modification
Hyracoidea(Hyraxes)
Sirenia(Manatees
and relatives)
Year
s ag
oM
illio
ns o
f yea
rs a
go
Dei
noth
eriu
m
Mam
mut
Steg
odon
Mam
mut
hus
Plat
ybel
odon
Bary
ther
ium
Moe
rithe
rium
Elephasmaximus
(Asia)
Loxodontaafricana(Africa)
Loxodontacyclotis(Africa)
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view
- Natural selection is differential reproductive success- Natural selection occurs through interactions between
the environment and the variability among individual organisms in a population
Figure 22.9 Variation in a population
Figure 22.11 Camouflage as an example of evolutionary adaptation
(a) A flower mantidin Malaysia
(b) A stick mantidin Africa
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view
- Natural selection is differential reproductive success- Natural selection occurs through interactions between
the environment and the variability among individual organisms in a population
- The product of natural selection is the adaptation of a population of organisms to their environment
7. What is artificial selection?- Selective breeding to encourage the occurrence of
desirable traits
Figure 22.10 Artificial selection
Terminalbud
Lateralbuds
Brussels sproutsCabbage
Flowercluster Leaves
Cauliflower
Flowerandstems
Broccoli Wild mustard Kohlrabi
Stem
Kale
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view7. What is artificial selection?8. What is the evidence for evolution?
- Homologous structures – similar structures with different functions show signs of evolution from a common ancestor, may be vestigial organs
Figure 22.14 Mammalian forelimbs: Homologous structures
Human Cat Whale Bat
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view7. What is artificial selection?8. What is the evidence for evolution?
- Homologous structures – similar structures with different functions show signs of evolution from a common ancestor, may be vestigial organs
- Comparative embryology - Pharyngeal gill slits- Post-anal tail
Figure 22.15 Anatomical similarities in vertebrate embryos
Pharyngealpouches
Post-analtail
Chick embryo Human embryo
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view7. What is artificial selection?8. What is the evidence for evolution?
- Homologous structures – similar structures with different functions show signs of evolution from a common ancestor, may be vestigial organs
- Comparative embryology - Pharyngeal gill slits- Post-anal tail
- Molecular biology
Figure 22.16 Comparison of a protein found in diverse vertebrates
Species
Human
Rhesus monkey
Mouse
Chicken
Frog
Lamprey14%
54%
69%
87%
95%
100%
Percent of Amino Acids That AreIdentical to the Amino Acids in aHuman Hemoglobin Polypeptide
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view7. What is artificial selection?8. What is the evidence for evolution?
- Homologous structures – similar structures with different functions show signs of evolution from a common ancestor, may be vestigial organs
- Comparative embryology - Pharyngeal gill slits- Post-anal tail
- Molecular biology- Biogeography – geographical distribution of species
Fig. 22.17 Different geographic regions, different mammalian “brands”
Sugarglider
AUSTRALIA
NORTHAMERICA
Flyingsquirrel
Chapter 22: Descent with Modification: A Darwinian View of Life
1. What do you know about evolution?2. What is evolution?3. What is paleontology?4. What was Lamarck’s view?5. What was Darwin’s view?6. Summarizing Darwin’s view7. What is artificial selection?8. What is the evidence for evolution?
- Homologous structures- Comparative embryology - Molecular biology- Biogeography – geographical distribution of species- Fossils
Figure 22.18 A transitional fossil linking past and present
top related