Evidence For Evolution Flashcards
(28 cards)
What are the two definitions of theory in science?
- Speculation, ideas, individual view. 2. Hypothesis that has been confirmed by observation or experiments and is accepted as accounting for the known facts.
What does macro-evolution refer to?
It refers to larger changes over a long-time scale.
What is natural selection?
Survival and reproduction determine the random survival of genes that lead to desirable characteristics.
What factors contribute to the gene pools in species?
Successful traits that enhance survival are the ones that persist in the gene pools of species worldwide.
What does anatomy reveal about species?
Species may share similar physical features because the feature was present in a common ancestor.
How do fossils contribute to our understanding of evolution?
They document the existence of now-extinct past species that are related to present-day species.
What is the significance of natural history in evolution?
Traits present in organisms can be understood only in view of their evolutionary path.
What does embryology tell us about organisms?
Traits present in organisms can be understood only in view of their evolutionary path.
What does biogeography study?
The global distribution of organisms reflects evolution and geological change.
What is homology?
Homology refers to traits that have descended from a common ancestral character, providing the basis for phylogenetic trees.
What is analogy in evolutionary biology?
Analogy describes the relationship of traits that have developed from unrelated ancestors through convergent evolution.
What is a fossil?
A fossil is the preserved remains of a once-living organism.
What do fossils teach us about evolution?
They show gradual change within lineages, splitting of lineages, existence of transitional forms, and that evolutionary change involves remodeling the old into the new.
What is the principle of superposition?
Deeper layers of rocks must have been laid down before shallower ones, and fossils can be used to cross-correlate different locations.
How can we determine a fossil’s age?
Fossils are generally found in sedimentary rocks, and we can calculate the date of formation of igneous rock using radioactive isotopes decay.
What does the fossil record indicate about species?
Fossils in older layers are more primitive than those in upper layers, and species change over time.
What is a vestigial trait?
A trait of a species that was an adaptation in its ancestors but has lost its usefulness completely or has been co-opted for new uses.
Example: Flightless birds, such as the dodo, evolved on islands without mammal or reptile predators.
What did Ernst von Baer discover about embryology?
The more closely related any two species are, the more similar their development as embryos.
What do vertebrate embryos share?
All vertebrates pass through similar developmental stages, including branchial arches, tails, and a simple heart and circulatory system.
What anatomical issues are unique to humans?
Fractured hips, bunions, hernias, shin splints, scoliosis.
What is an example of bad design in human anatomy?
The recurrent laryngeal nerve, which is a branch of the vagus nerve that supplies motor function and sensation to the larynx.
What are anatomical imperfections?
They can be explained by the fact that evolution doesn’t start from scratch; organisms evolve features present in ancestors.
What is biogeography?
The study of what organisms live where on Earth and why.
What are biogeographical patterns?
Regions with identical climates can have different floras and faunas, and geographical barriers can create breaks between taxonomic groups.
