Evolution Flashcards
What is homology?
The presence of features that are similar across species, and have the similar function or purpose.
What is homologous structure?
Both evolved from a similar ancestor.
What is comparative embryology?
Looking at the similarities and differences between embryos of different species.
What does DNA hybridization test?
Measures the degree of genetic similarity between pools of DNA sequences.
What is relative dating?
Knowing that deeper layers of rock and the fossils in them are older, and shallower layers are younger.
what does fossil dating tell us?
Determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.
What was the name of the initial giant landmass that existed 225 million years ago?
Pangaea
How much do tectonic plates move each year?
A few centimeters (10 cm)
What is biogeography?
The study of the geographical distribution of species.
What is NOT something fossils can help us discover?
Whether ancient organisms were poisonous.
What conditions are required for the formation of fossils?
The organism must not be eaten by predators. The organism must not decay by bacteria or exposure to oxygen. The organism must be buried by sediment quickly.
What is Absolute dating?
Testing the decay of radioactive components in fossils.
The fossil record of Earth shows us what?
timeline of evolution via all the organisms discovered as fossils.
What does DNA hybridization test?
The similarities between DNA of different species.
What are the methods of analyzing chemical comparisons?
Comparing sequences and DNA hybridization
What is Darwin’s theory of evolution?
Changes occur in a species by natural selection which causes the species to diverge from common ancestors.
What is a common ancestor?
A ancestral species that multiple present species descended from.
Why do the beaks of the finches in the Galapagos all look slightly different?
Different selection pressures.
How can we test if two isolated populations are different species?
We see if they can inbreed and produce viable offspring
What is natural selection?
The process through which populations of living organisms adapt and change.
What is variation?
A range of different phenotypes.
With a lack of genetic diversity or small variation in phenotypes in a population, what would happen if the selection pressures changed?
The population would most likely die out.
How does isolation play a role in natural selection?
Prevents inbreeding and gene flow.
When exposed to a new or changing environment, the organisms that are best suited to the environment are most likely to:
Survive and reproduce.
