Evolution: An Introduction Flashcards
What is evolution ?
Change in species characteristics over time
Species accumulate differences from their…
Ancestors as they adapt to different environments but also have many similar features in common because of shard ancestory
Evolution in 300 BCE
Recognized “affinities” among organisms based on observations of nature, species thought of as find and unchanging
Evolution in the 1700s
Linnaean taxonomy was sought to classify life’s diversity and used nested classification system;
Scientists developed scientific naming system still used today
Evolution in the late 1700s through early 1800s
Fossils in older rock layers did not look like current species; so,e species appeared while others disappeared from one layer to the next
Jean-Baptiste de Lamarck proposed…
The first mechanism for how life changes over time
The idea was that parts if the body that were used more become larger and stronger, and those that aren’t deteriorate then organisms pass it on to their offspring
Who were the fathers of evolution?
Brakes Darwin and Alfred Russel Wallace came up with the theory of evolution by natural selection
What is natural selection?
The mechanism that drives evolutionary change, process where individuals with certain inherited traits tend to survive and reproduce at higher levels then other individuals because of those traits
For evolution by natural selection to occur
Variation, heritability and differential fitness must exist in the population
What is adaptations ?
Inherited characteristics of organisms that increase their survival and reproduction in certain environments
What is fitness?
The ability of individuals to survive and produce offspring relative to other individuals in the population
What is a genotype?
The genetic makeup/code of an individual
What is a phenotype?
The expression of the genotype that are visible and can be observed
Natural selection acts on individuals but it’s consequences occur in…
Populations
Natural selection acts on phenotypes but evolution consists of changes in…
Allele frequencies
