Chapter 21 Flashcards
Who developed the theory of Evolution?
Charles Darwin
What is Natural Selection?
When certain traits become more or less popular over generations through reproductive success
What are the 3 conditions for natural selection?
- Phenotypic variations exist in population
- Variation leads to differences in offspring
- Phenotypic variation can be passed to offspring
What are peppered moths an example of?
natural selection
What is artificial selection?
when humans breed for certain traits
What are the 3 things needed for rock fossil formation?
- organism is buried in sediment
- calcium in bone or other hard tissue mineralizes
- Surrounding sediment hardens to form rock
What are transitional fossils?
Fossils that show traits from both ancestors and decedents; intermediates
What is carbon dating?
measuring the radioactivity of carbon in a fossil to determine its age
What are homologous structures?
different structures derived from the same body part of an ancestor
Embryos are often ________ in early stages for different organisms.
similar
What are vestigial structures?
structures that have no apparent function passed down form an ancestor
What are pseudogenes?
Genes that are unable to code for proteins; previously functioning genes for traits that have disappeared
What is convergent evolution?
similar forms of evolution that happened in different, separate areas due to similar circumstances
