Evolution Flashcards
Selection pressures
Predators
Food
Disease
Climate
Jean Baptiste Lamarck
Inheritance of acquired characteristics
Characteristics of individuals change over a lifetime
These changes are passed to next generation
Charles Darwin
Evolution by natural selection Environment selves from existing variation These survive and pass on genes Offspring acquire these genes =The mechanism of evolution
Theory of evolution
Mall species have evolved from simple life forms and natural selection causes less adapted life forms to become extinct
Selective breeding
Breeding only those individuals with desirable characteristics (artificial selection)
Example of selective breeding
Pedigree dogs
Cloning
Any procedure that produces genetically identical offspring
Types of cloning
Micropropagation and cuttings
Reproductive cloning
Transfer of a nucleus from a somatic cell of donor A to an egg cell of donor B that’s has no nucleus to form a diploid zygote with A’s DNA
Developing embryo is implanted into uterus of foster mother
Fossils
Mineralised or otherwise preserved remains of animals, plants and other organisms
How are fossils formed
Harder parts of animals or plants are replaced by minerals over a long period of time
Animals or plants trapped in ice or Amber
Casts or impressions can be found
What can a fossil tell us
When animals lives
Evolution of animal
Numbers of animals that existed
What can fossils not tell us
Exact appearance
Gaps in fossils record
Extinction
The permanent loss of an animal from the the Earth
Mass extinction
Loss of a number of species at the same time
