Life history traits are integrated biological characteristics of an organism that determine the timing and allocation of resources to growth, reproduction, and survival, and thus shape its life cycle. They include age and size at maturity, fecundity, reproductive schedule (e.g., semelparity vs. iteroparity), offspring size and number, growth rate, and lifespan. As a composite process outcome of development, physiology, and behavior under genetic and environmental control, life history traits are central to life history theory, which models how natural selection optimizes trade-offs among these traits to maximize fitness in specific ecological contexts.
In a new study, appearing in Proceedings of the Royal Society B: Biological Sciences, scientists selectively bred Japanese quails into two groups: laying either relatively large or small eggs. As the quails don't do much ...
Plants & Animals
21 hours ago
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Between 280 and 200 million years ago, a group of animals evolved which would eventually give rise to mammals, including humans: the therapsids. They were first described more than 150 years ago, based on fossils from South ...
Evolution
Apr 12, 2026
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Researchers have documented several cases of spatial orientation in tarantulas living both in trees and in underground burrows. Spatial orientation refers to the ability of an animal to understand where it is in three-dimensional ...
Plants & Animals
Apr 10, 2026
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A remarkable new discovery is shedding light on one of the greatest survival stories in Earth's history, and answering a decades-old scientific mystery. Lystrosaurus, a hardy, plant-eating mammal ancestor, rose to prominence ...
Evolution
Apr 9, 2026
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For mating male octopuses, one limb is more important than all others. That is the third right arm or hectocotylus, which is used to transfer sperm to the female because the penis cannot do it directly. Losing the limb can ...
How can we predict species' responses to always-arising changes in our world? A long-term ecological study from Yokohama National University researchers suggests the answer may lie in a few small simple biological traits. ...
Ecology
Apr 6, 2026
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"It takes a village to raise a child" doesn't apply merely to humans. Many species of mammals, birds, fish, and various invertebrates have evolved complex social care systems known as cooperative breeding. In these animal ...
Evolution
Apr 5, 2026
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South of Fall Creek by the edge of the woods, the moths would gather. They were, of course, drawn by light—set out by a researcher working in Cornell University's old Insectory building. In 1889, the lure came from a kerosene ...
Plants & Animals
Mar 17, 2026
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A study published in Ecological and Evolutionary Physiology reveals a surprising link between cellular aging markers and survival in black-legged kittiwakes (members of the gull family). In the work titled "Who's coming home? ...
Plants & Animals
Feb 24, 2026
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When most people think about natural selection, they imagine individuals competing with one another: The fastest animal escapes predators, the strongest plant produces more seeds, and the most resistant bacteria better survive ...
