What occurs when some elephants in a population migrate?
genetic drift through the bottleneck effect. What occurs when some elephants in a population migrate into another area and join another population? Gene flow does not occur.
What is the model for rapid changes separated by no changes over time?
The theory of punctuated equilibrium states that evolutionary change is characterised by short periods of rapid evolution followed by longer periods of stasis in which no change occurs.
What type of selection would include the evolution of a long neck in giraffes?
What is the relationship between speciation and the theory of punctuated equilibrium?
what is the relationship between speciation and the theory of punctuated equilibrium? the theory of punctuated equilibrium states that speciation occurs suddenly in geologic time and is followed by long periods of little evolutionary change or speciation.
What is the main difference between gradualism and punctuated equilibrium?
Both theories describe the rates of speciation. For Gradualism, changes in species is slow and gradual, occurring in small periodic changes in the gene pool, whereas for Punctuated Equilibrium, evolution occurs in spurts of relatively rapid change with long periods of non-change.
Why is punctuated equilibrium important to evolution?
Punctuated equilibrium predicts that a lot of evolutionary change takes place in short periods of time tied to speciation events. Also, their small population size means that genetic drift influences their evolution. The isolated population undergoes rapid evolutionary change.
Why are birds an example of convergent evolution?
Birds and bats have homologous limbs because they are both ultimately derived from terrestrial tetrapods, but their flight mechanisms are only analogous, so their wings are examples of functional convergence. The two groups have powered flight, evolved independently. Their wings differ substantially in construction.
What is regressive evolution?
REGRESSIVE EVOLUTION IN CAVE ANIMALS Regressive evolution refers to the loss of useless characters over time. It is a critical evolutionary process in all organisms. For example, humans would be as hairy and tailed as other primates if regressive evolution did not prune unused ancestral traits.
What is genetic convergence?
Convergence: independent appearance of the same trait in different lineages. Convergent recruitment: the process of homologous gene becoming recur- rently responsible for a novel function. Convergent substitution: replacement of the same ancestral character (e.g. amino acid) by an identical character.
What is meant by homologous chromosome?
A pair of chromosomes made up of two homologs. Homologous chromosomes have corresponding DNA sequences and come from separate parents; one homolog comes from the mother and the other comes from the father. Homologous chromosomes line up and synapse during meiosis.