An examination of 3 reasons why some species of nonhuman organisms breed synchronously: Optimal Resource Availability; Social Foraging; and, Avoiding Predation.
An examination of sexual selection in relation to speciation, including runaway sexual selection and sensory exploitation.
Deleterious effects of inbreeding in lions, and mechanisms of incest avoidance in zebra finches via female choice of male song, and incest compensation in shore birds via extra-pair mating.
When it comes to sexual selection, males court females, and females choose with whom to mate (with a few exceptions). Thus, female choice of mate is critical, and here we describe examples of this as well as related phenomena such as the Handicap Principle, disruptive selection, and sexual dimorphism not caused by sexual selection.
The Darwinian concept of sexual selection, explored through examples of sexual dimorphism, how females can benefit by being choosy when selecting a mate, what cues females might use to assess potential mates.
Allelochemics are semiochemicals (i.e., chemicals that have either communicative value or anti-predator benefits) that communicate between different species. Three subclasses of allelochemics are allomones (that benefit the sender), kairomones (that benefit the receiver), and synomones (that benefit both the sender and receiver). Examples are shown of each of these substances.
The reproductive behavior of ring doves has been investigated thoroughly beginning with the pioneering studies by Daniel S. Lehrman and his associates. His work, which is described here, nicely illustrates how external environmental factors cause the release of hormones, which, in turn, triggers behaviors, which, in turn cause the release of other hormones that affect all aspects of reproduction (courtship, incubation, parenting).
The process of domestication as analogous to natural selection, examples of domesticated animals, including an historical perspective leading back to Darwin. Also, experimental studies of artificial selection, and the steps necessary to create domestic breeds.
An examination of changes in timing of developmental events over evolutionary time—a phenomenon known as "heterochrony," which covers both accelerated development across evolution as well as neoteny, a slowing down of developmental events.
Is the rate of evolutionary change gradual or rapid? This screencast explores the Darwinian rate of gradualism vs. salvationism, or punctuated equilibrium. The two are not mutually exclusive.