Struggle for existence High birth rates and shortage of lifes needs Food and living space Fitness ability to survive and reproduce in your environment Survival of the fittest Adaptation Characteristic to ID: 530232
Download Presentation The PPT/PDF document "Darwin’s Case For Evolution" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Darwin’s Case For EvolutionSlide2
Struggle for existence
High birth rates and shortage of life’s needs
Food and living space
Fitness – ability to survive and reproduce in your environmentSurvival of the fittestSlide3
Adaptation
Characteristic to
increase fitness
Successful adaptations allow one to be better able to survive and reproduceinheritable Slide4
Evidence for Evolution
Darwin argued that living things have been evolving on Earth for millions of years. Evidence for this process could be found in the fossil record, the geographical distribution of living species, homologous structures of living organisms, and similarities in early development. Slide5
Paleontology
Study of the fossil record as a picture of life’s changes
Comparison of the different layers of
rockDarwin learned through his studies that fossils formed in different layers of rock were evidence of gradual change over time.
Different layers even provided evidence of how a specific species changed over time. Slide6
Fossil
Evidence
physical remains
http://darwiniana.org/horses.htm
45 second movieSlide7
Biogeography
The distribution of animals and plants in an areaSlide8
Under different pressures, once similar organisms could wind up different over long periods of
time and many generations.
Beaver
NORTH AMERICA
Muskrat
Capybara
SOUTH AMERICA
Coypu
Beaver
Muskrat
Beaver and
Muskrat
Coypu
Capybara
Coypu and
CapybaraSlide9
Pinta Island
Intermediate shell
Pinta
Isabela Island
Dome-shaped shell
Hood Island
Saddle-backed shell
Hood
Floreana
Santa Fe
Santa Cruz
James
Marchena
Fernandina
Isabela
Tower
Giant Tortoises of the Galápagos Islands
DRY LANDSCAPE
LUSH
VegetationSlide10
Morphology
Study of the form and structure of living organisms
Some organs are present in many organisms with similaritiesSlide11
Turtle
Alligator
Bird
Mammals
Typical primitive fish
4. Homologous Body Structures
common genes
Structures which have different mature forms but develop from similar embryonic tissuesSlide12
Morphology
Homologous structures
Characteristics which are shared by related species
Different mature structure, but similar in developmentEvidence of a common ancestor, and descent with modificationSlide13
Vestigial Organs
Organs that are remnants of earlier stages in life
Example: Human
appendixSlide14
Embryology
Comparing development, especially
vertebrates (animals with backbones)
Similar development common ancestor Slide15
Similar
embryonic development
*
early stages of development, chickens, turtles, and rats look similar
*
share a common ancestry (and common developmental genes)Slide16
Guess the Embryo: http://www.pbs.org/wgbh/nova/evolution/guess-embryo.html
Click Launch Interactive and work through the program