Evolutionary Biology

Organisms that are better adapted to their environment tend to survive and produce more offspring, transmitting their advantageous traits to the next generation.

Members of a species get smaller or bigger depending on the resources available in the environment (Island Rule).

An organism never returns exactly to a former state, even if it finds itself placed in conditions of existence identical to those in which it has previously lived.

Kin selection causes genes to increase in frequency when the genetic relatedness of a recipient to an actor multiplied by the benefit to the recipient is greater than the reproductive cost to the actor ($rB > C$).

Species must constantly adapt, evolve, and proliferate in order to survive while pitted against ever-evolving opposing species.

In the absence of recombination (as in asexual reproduction), an accumulation of irreversible deleterious mutations results.

The vast majority of evolutionary changes at the molecular level are caused by random drift of selectively neutral mutants rather than by natural selection.

Organisms not closely related independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

The ability of one genotype to produce more than one phenotype when exposed to different environments.

A mechanism for specific selection for general learning ability, where an organism's ability to learn new behaviors affects its reproductive success and eventually the genetic makeup of the species.

The fusion of Mendelian genetics with Darwinian evolution that resulted in a unified theory of evolution.

Evolutionary development is marked by isolated episodes of rapid speciation between long periods of little or no change.

Natural selection arising through preference by one sex for certain characteristics in individuals of the other sex.

In most species, variability in reproductive success is greater in males than in females.

A strategy which, if adopted by a population in a given environment, cannot be invaded by any alternative strategy that is initially rare.

Evolution occurs uniformly and by the steady and gradual transformation of whole lineages (anagenesis).

The probability of extinction is roughly constant over the life time of a group of organisms.