Evolution notes Flashcards
Scientific definition of species?
members inbreed, shared gene pool, reproductively isolated from other species, do produce fertile offspring
Who was Carolus Linnaeus?
He was wrong, believed in creation and that species are “ideal” in form and function
Who was Alfred Wallace?
Proposed idea of natural selection but didn’t have detailed support of the theory, similar ideas as Darwin
Jean-Baptiste de Lamarck
his ideas were proved wrong by Weissman, believed in creation, use vs disuse theory, believed in the idea inheritance of acquired characteristics
What do we know about phenotypes and genotypes?
Phenotypes are no inherited but genotypes may be if they take place in the gametes
Who was Charles Darwin?
Developed the theory of evolution by natural selection, he understood the earth was very old
What are the 4 components of natural selection?
1) variation is inherited
2) more individuals are produced than survive
3) some individuals are better adapted than others
4) an increasing proportion of individuals in succeeding generations have adaptive characteristics
Evidence of Evolution?
Artificial selection, Fossil record, comparative anatomy, embryology, Genetics, bio geography, convergent evolution
What are Adaptations?
characteristics or traits that help an organism survive and reproduce in its environment.
What is biogeography?
study of the distribution of living organisms across different regions of the Earth, both in the present day and throughout history
If there is one island near the mainland and another island further from the mainland which island will have more similar species to the mainland.
The closer island because it is easier to migrate there and has a similar environment.
Fossil Record?
collection of fossils discovered, shows evidence of past life and common ancestors.
what are fossil record transitional forms?
are fossils of organisms that show traits of two different groups of species. For example tiktolak is considered a transitional fossil that shows features of both fish and the first land vertebrates
What is comparative anatomy?
study of similarities and differences in the structures of different organisms, similarity suggests a common ancestry
What are homologous traits?
same structure, different functions
What are analogous traits?
Different structures, same function
What is comparative embryology?
study of the development of embryos from different species, with the aim of understanding how they develop and how their developmental processes are related
Biochemistry?
study of the chemical processes and substances that occur in living organisms
What are vestigial structures?
A trait that used to be useful to a species however over time the species has adapted and the trait is no longer used. Ex. humans- tailbone but no tail
What is sexual selection?
the organisms that are better at finding mates and having babies because of their traits, pass on those traits to future generations
What is sexual dimorphism?
males and females of the same species have a different appearance. Ex. male peacocks are bright, colorful, and large while females are more brownish colored
What is convergent evolution?
Two different organisms both evolve similar traits as a result of adapting to similar environments. Ex. sharks and dolphins
What is coevolution?
Process by which two or more species influence each other’s evolution over time. Ex. cheetahs and gazelles
Weakness’s of Darwin’s theory?
couldn’t explain the source of variation even though he could observe it
What is the modern theory if evolution?
Darwin’s ideas but with new knowledge of DNA, meiosis, and mutations
What is geographic isolation?
a population of organisms is physically separated from other populations of the same species due to geographical barriers like mountains, rivers, oceans, or deserts.
What can geographic isolation lead to?
speciation of millions of years
What is allopatric speciation?
New species are created caused by geographic isolation
What is genetic drift?
change that randomly takes place in a gene pool, more drastic in small populations, makes microevolution more likely
What are the types of selection?
Directional, Disruptive, stabilizing
What is direction selection?
type of natural selection where individuals with traits at one extreme of a particular range are favored, leading to a shift in the population’s traits over time. Ex. industrial melanism study by HBD kettlebell
What is Disruptive selection?
type of natural selection that favors individuals at both extremes of a trait distribution, while individuals with intermediate traits are selected against. Ex. land snails
What is stabilizing selection?
type of natural selection that favors individuals with traits that are average or intermediate, and selects against individuals with extreme traits. Ex. human babies, 2-10.8 lbs
What is adaptive radiation?
emergence of many species from a common ancestor introduced to new and diverse environments
