Biological variation in populations is the process by which genetic and phenotypic differences arise, are maintained, and change in frequency among individuals within a species. It results from the combined action of mutation, recombination, gene flow, genetic drift, and natural and sexual selection, acting on genomes across generations. At the population level, this variation underlies differences in traits such as morphology, physiology, behavior, and fitness-related characteristics, and is quantified using measures like allele frequencies, heterozygosity, and quantitative trait distributions. Population-level biological variation provides the raw material for adaptive evolution and influences population dynamics, speciation potential, and responses to environmental change.
If you follow media coverage of koalas, you could be forgiven for feeling confused. Recent stories describe a "koala paradox": endangered in the north of Australia, abundant in the south; genetically diverse in some regions, ...
Plants & Animals
Mar 6, 2026
0
0
Animals of the same species don't always look the same. From birds with different beak shapes to mammals that vary in size or color, populations living in different places can often look very different.
Evolution
Mar 1, 2026
0
1
The human genome is a rich, complex record of migration, encounters, and inheritance written over thousands of millennia. Genomic research by members of Sarah Tishkoff's lab at the University of Pennsylvania are revisiting ...
Evolution
Feb 26, 2026
1
2
Whether people follow a general trend when choosing a partner or consciously decide against it has a noticeable impact on the diversity of phenotypes to choose from. This is shown by a new study by the University of Würzburg.
Evolution
Feb 24, 2026
0
0
Researchers from the USDA's Agricultural Research Service (ARS) and the University of California, Davis, are helping beekeepers protect their colonies from destructive varroa mites. In a new study, the researchers investigate ...
Plants & Animals
Feb 19, 2026
1
71
A study reveals that sticklebacks with complete bony plates have survival rates several percentage points higher than those with reduced plates, indicating ongoing natural selection. Moreover, the strength of selection appears ...
Evolution
Feb 11, 2026
0
2
Cucumber is an economically important crop worldwide, ranking as the third most-produced vegetable after tomatoes and onions. Yet breeding improved varieties—plants that are more resilient, produce better-shaped fruit, ...
Plants & Animals
Feb 10, 2026
0
2
A new genetic study examines an unusually large hybridization event that followed the Fukushima nuclear accident, when escaped domestic pigs bred with wild boar. The research shows that domestic pig maternal lineages sped ...
Plants & Animals
Feb 9, 2026
0
172
Every ecosystem is shaped by billions of invisible battles: organisms competing for light, nutrients, space, or mates. These competitive interactions determine which species survive, how they evolve, and how vibrant and resilient ...
Evolution
Feb 3, 2026
0
0
Microbes often display cooperative behavior in which individual cells put in work and sacrifice resources to collectively benefit the group. But sometimes, "cheater" cells in the group may reap the benefits of this cooperation ...
Evolution
Jan 8, 2026
0
43
