evidence of evolution fossil record geological distribution of organisms homologous structures...
TRANSCRIPT
![Page 1: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/1.jpg)
![Page 2: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/2.jpg)
![Page 3: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/3.jpg)
Evidence of Evolution
Fossil recordGeological Distribution
of organisms
Homologous structures
Comparativeembryology
Which is
Com
posed of
indicating
implying
implying
Physical remains of
speciesSimilar genes
Common ancestral species
Similar genes
![Page 4: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/4.jpg)
![Page 5: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/5.jpg)
Natural selection
• Natural selection can affect the distributions of phenotypes in any of three ways
• Directional selection
• Stabilizing selection
• Disruptive selection
![Page 6: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/6.jpg)
Directional selection
• When individuals at one end of the curve have higher fitness than individuals in the middle or at the other end, directional selection takes place.
• The range of phenotypes shifts as some individuals fail to survive and reproduce while others succeed.
![Page 7: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/7.jpg)
![Page 8: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/8.jpg)
![Page 9: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/9.jpg)
Directional selection
![Page 10: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/10.jpg)
Disruptive selection
• When individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle, disruptive selection takes place.
• In such situations, selection acts most strongly against individuals of an intermediate type.
![Page 11: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/11.jpg)
Disruptive selection
Disruptive Selection
Largest and smallest seeds become more common.
Nu
mb
er o
f B
ird
sin
Po
pu
lati
on
Beak Size
Population splits into two subgroups specializing in different seeds.
Beak Size
Nu
mb
er o
f B
ird
sin
Po
pu
lati
onKey
Low mortality, high fitness
High mortality, low fitness
![Page 12: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/12.jpg)
Stabilizing selection
• When individuals near the center of the curve have higher fitness than individuals at either end of the curve, stabilizing selection takes place.
• This situation keeps the center of the curve at its current position, but it narrows the overall graph This situation keeps the center of the curve at its current position, but it narrows the overall graph
![Page 13: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/13.jpg)
Stabilizing selection
![Page 14: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/14.jpg)
Founder effect
• A situation in which allele frequencies change as a result of the migration of a small subgroup of a population is known as the founder effect.
• This can lead to new species!
![Page 15: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/15.jpg)
Founder effect
Sample of Original Population
Founding Population A
Founding Population B
Descendants
![Page 16: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/16.jpg)
Homologous body structures
• Further evidence of evolution can be found in living animals. By Darwin’s time, researchers had noticed striking anatomical similarities among the body parts of animals with backbones.
![Page 17: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/17.jpg)
![Page 18: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/18.jpg)
![Page 19: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/19.jpg)
![Page 20: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/20.jpg)
![Page 21: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/21.jpg)
Comparative embryology
• The early stages, or embryos, of many animals with backbones are very similar.
• It is clear that the same groups of embryonic cells develop in the same order and in similar patterns to produce the tissues and organs of all vertebrates.
![Page 22: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/22.jpg)
Similar Embryos
![Page 23: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/23.jpg)
The Process of Speciation
• As new species evolve, populations become reproductively isolated from each other.
• Behavioral isolation– Different courtship rituals
• Geographic isolation– Rivers, mountains, body of water
• Temporal isolation– Different time of reproduction
![Page 24: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/24.jpg)
Vicariance
![Page 25: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/25.jpg)
results from
which include
produced by produced byproduced by
which result in
which result in
Reproductive Isolation
Isolating mechanisms
Behavioral isolation Temporal isolationGeographic isolation
Behavioral differences Different mating timesPhysical separation
Independentlyevolving populations
Formation ofnew species
![Page 26: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/26.jpg)
coevolution
• Sometimes organisms that are closely connected to one another by ecological interactions evolve together.– Flowers and their pollinators– Anemones and anemonefish (clown fish)– Ants and trees– Mantids and plants or flowers– Mitochondria/humans & chloroplast/plants?
![Page 27: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/27.jpg)
![Page 28: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/28.jpg)
![Page 29: Evidence of Evolution Fossil record Geological Distribution of organisms Homologous structures Comparative embryology Which is Composed of indicating](https://reader036.vdocuments.site/reader036/viewer/2022081506/56649cb45503460f94977ac5/html5/thumbnails/29.jpg)
The End