evolution

• The two processes that could cause variations are crossing over and mutation
• the fact that at least one species of resistant bacteria has developed for almost every antibiotic is evidence that the bacteria has adapted and could be evolving into different species
• these organisms are homologous because they belong to organisms that probably evolved form a common ancestor

  
• homologous structures might be the result of a change in allele frequencies over successive generations. They probably continued because they were beneficial in a particular environment
• a short type of sunflower might be identified as a new species because they are unable to breed with other sunflowers from the original population
• if over a period of years the bark on trees became spotted, the unique characteristic that beetles would show through biological adaptation is that they'd become spotted
• with the theory of natural selection, some individuals are more likely to survive an reproduce because they are better adapted to their environment than others
• variation is a factor within species that increases the likelihood that some members of a species will survive when environmental conditions change
• in order for evolution to occur, there must be natural selection
• stabilizing selection favors average individuals in a population
• scientists can estimate at what point various groups of organisms diverged evolutionarily from one another by using DNA evidence
• Charles Darwin personally observed finches of the same species while traveling through the Galápagos Islands
• turtle and human embryos have a tail is true because of comparative embryology
• Polar bear fur is better camouflage on ice than brown fur is an example of adaptation
• after returning from his voyage, Darwin assumed south African finches changed after coming to the Galápagos Islands
• evolution is the change of species over time
• cheetahs suffered a dramatic drop in population, they rebounded in number to create a population of genetically similar animals. this is an example of bottleneck
• the first conclusion Darwin made after returning was that natural selection was the evolutionary mechanism for species change
• a feather is a bird trait that is an example of a derived trait
• cytochrome c provides a broad-ranged comparison of evolutionary relationships because the molecule experienced little change over long periods of history
• if 100 people isolated themselves on an island, their genetic make up after several generations would be determined by the founder effect
• Darwin referred to the selective breeding of domesticated animals as artificial selection
• the evolution of an elongated beak in birds is an example of adaptation
• peacocks developing large tails, as a result of long-tailed males being selected more frequently by females is called sexual selection
• the breeding of larger tomato plants by farmers is artificial selection
• the speciation of 5 modern tiger species from one ancestral species is called evolution
• studying the structures of organisms during early stages of development is called comparative embryology
• if an organism doesn't adapt to a certain feature that is necessary for survival, it'll result in death
• the DNA similarities within a population that appears as though they have been inbred is called bottleneck
• genetic equilibrium is constant allele frequencies in a population
• bottleneck is the reduction in a number of alleles, resulting in a population that is genetically similar
• founder effect is a small, separated population with a unique genetic make up
• this is an example of directional selection