population ecology: Quick Facts

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Photos

A herd of wildebeest, including calves, moves across a dusty savanna in Africa with scattered trees visible in the background.

K-selected species

Graph showing three survivorship curves: Type I (red, with human figures) has high survival early and drops steeply at old age; Type II (blue, with a bird) declines steadily; Type III (green, with a plant) drops sharply early, then levels off. X-axis is age, y-axis is number of survivors on a log scale.

Galapagos cactus finch (Geospiza scandens)

Side-by-side line graphs compare exponential and logistic population growth. The exponential growth graph shows a curve rising steeply upward, while the logistic growth graph shows an S-shaped curve leveling off at the carrying capacity of the environment.

A line graph with red and blue shaded areas shows cyclical rises and falls in the populations of snowshoe hares and lynx from 1855 to 1925, illustrating how hare population peaks are followed by lynx population peaks. Small illustrations of a running snowshoe hare and a lynx appear above the graph.

invasive prickly pear cactus in Australia

biological control of invasive prickly pear cactus in Australia

Edith's checkerspot butterfly

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Topics

population genetics population species ecology community ecology systems ecology autecology patch dynamics Phenology geographic mosaic theory of coevolution

Key People

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Thomas Park

American animal ecologist

greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)

Biology Bonanza

Chutes d'Ekom - a waterfall on the Nkam river in the rainforest near Melong, in the western highlands of Cameroon in Africa.

Ecosystems