Evolution Unit Test Flashcards
What is a theory?
A hypothesis or series of hypotheses that have been supported by repeated tests. It is a valid explanation of a phenomenon.
What must a theory be?
Explanatory, Predictable (guess what will occur accurately), Testable
What are the types of mutations?
Harmful- more common than beneficial; selected against and have no influence on populations
Beneficial- relatively rare; favored by natural selection; tend to accumulate in populations over time (opposable thumbs)
Neutral- provide no benefit or harm; will not be selected upon if neither beneficial or harmful (eye color)
What is selective breeding?
Directive breeding in which individuals that exhibit a particular trait are chosen as parents of the next generation (aka artificial breeding)
What is the age of the earth?
4.5 billion years old
What is absolute dating?
Determining a specific age of an object or event; a scientific method
What is relative dating?
The science of determining events relative to each other; used for materials w/o radioisotopes
What is radiometric dating?
Uses radioisotopes to determine the age of fossils
Radioisotopes - an atom w/ an unstable nucleus capable of undergoing decay
What is the fossil record?
Fossils- ancient remains, impressions or traces of an organism that have been preserved in rocks or other mineral deposits
Fossils allow us a snapshot of early species; helps us understand where new variations have arisen; suggest transitions between species
What is the plate tectonics theory?
Theory that describes large scale movements and features or earths crust; earths crust is made of plates that move around very slowly
What would the plate tectonics theory explain?
Species would have lived together where all three continents connected at some point in history (Pangea)
What is biogeography?
The scientific study of the geographic distribution of organisms based on both living species and fossils (where they were and where they are)
Fossil evidence suggests Pangea was real
What are homologous features?
A structure with a common evolutionary origin that may serve different functions in modern species
Ex: forearms
What are analogous features?
A structure that performs the same function as another but is not similar in origin or anatomical structure
Ex: dolphin and shark fins, birds and bats flying
What are vestigial features?
A non-functioning, or only marginally functioning, structure that is homologous to a full functioning structure in closely related species
Ex: whales have tiny hip bones and leg bones
What is Charles Darwin’s theory?
When traveling to South America, specifically Argentina, Darwin found new species that looked like many of the species found in South America; also found fossils resembling species in the same area; found his finches (13 species of finches)
Created the theory of evolution (the origin of species)
What is modern evolutionary synthesis?
Modern theory of evolution; takes into account all branches of biology (includes genetics and plate tectonic theory)
How are evolution and genes related?
Genes code for different raids and evolution acts on genes
What is gene duplication?
Gene mutation can often be harmful; if there’s an extra copy of a gene that mutates, the healthy copy makes sure the cell functions properly; often neutral
What are homologous genes?
Homologous genes share a common ancestor but have mutated over time
The more closely related 2 species are, the more similar their homologous genes will be
What are pseudogenes?
Vestigial genes undergone mutations and no longer serves a purpose
What is natural selection?
The way in which nature favors the reproductive success of some individuals within a population over others (some individuals are more likely to pass their genes along than others)
What does reproduction have to do with natural selection?
Organisms have features that make them better suited to an environment and are more likely to reproduce and these features are more likely to persist in a population
What are three ways a species can be successful?
- Better suited at gathering resources in a population
- Better able to avoid predators
- Ability to adapt to a unique environment