BIL 330 Lecture Notes - Lecture 16: Semelparity And Iteroparity, Guppy, Marsupial
Document Summary
The trinidadian guppy is common to the streams of trinidad. In lower stream reaches, guppies have short life expectancies because they face predation by pike cichlids and killifish. In predator-free, higher elevation streams, guppies have long life expectancies: differences in life expectancies correlate with aspects of life history. Same species just different biotic context aka organismal (not streams = abiotic) In almost all species, individuals eventually experience a decline in body condition followed by death (i. e. , senescence). Organisms differ in the number of times they reproduce before senescence. Semelparity: when organisms reproduce only once during their life; relatively rare in vertebrates, but common in insects and plants. https://www. youtube. com/watch?v=cjo8p0tdqww. Iteroparity: when organisms reproduce multiple times during their life; common among birds, reptiles, mammals, and amphibians. Annual: an organism that has a life span of one year. Perennial: an organism that has a life span of more than one year.
