Biological evolution is the heritable change in characteristics of biological populations over successive generations, driven by mechanisms such as mutation, recombination, genetic drift, gene flow, and natural and sexual selection. It operates through changes in allele frequencies within gene pools, constrained and shaped by developmental, physiological, and ecological contexts. Evolutionary processes generate adaptation, diversification, and extinction, producing hierarchical patterns from microevolutionary shifts within populations to macroevolutionary dynamics among lineages. At the molecular level, evolution involves sequence variation, genomic rearrangements, and changes in gene regulation, which collectively underlie phenotypic diversity and the emergence of complex biological organization.
A University of Texas at Austin-led team has reconstructed the most detailed map to date of the molecular machines that carried out the functions of life in an ancient ancestor that gave rise to all complex life on Earth, ...
Molecular & Computational biology
May 27, 2026
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145
If you look at the trees as you're driving on the Trans-Canada Highway toward Banff National Park, you will see Englemann spruce on the cooler, wetter northeast-facing slopes of the Three Sisters. Across the valley—on the ...
Plants & Animals
May 26, 2026
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18
In evolutionary biology, all life on Earth is theoretically part of a single phylogenetic tree, indicating common ancestry. This model suggests that every living organism can be traced back to a distant common ancestor. However, ...
Molecular & Computational biology
May 26, 2026
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25
NASA had a big—and little—problem. For a small satellite, the agency needed a tiny antenna, with very specific communication capabilities and very strict limits on size and weight. The agency gave the problem to a design ...
Evolution
May 26, 2026
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30
The outer regions of the brain, the cortex, have specific layers of different cells—neurons—that are similarly ordered among all mammals, from tiny mouse brains to huge elephant brains. However, the proportions of different ...
Evolution
May 26, 2026
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16
Transposons, DNA sequences that can self-replicate and move (jump) throughout the genome, are widespread and can affect cell survival if left unchecked. Cells control these "jumping genes" by silencing them, but little was ...
Cell & Microbiology
May 25, 2026
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40
Almost all animal species—including humans—have blood cells, but between different species our blood tells different stories. The lineage and components of blood cells vary widely, and this variety is a testament to how animals ...
Evolution
May 25, 2026
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47
For most of the 20th century, the model of human origins was a tree: with the trunk dividing into branches, and then twigs. Each species of human relative (hominin) was a neat, single branch.
Evolution
May 23, 2026
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76
A research team from Kiel University has demonstrated which specific cellular mechanisms lead to the targeted weakening of bacterial pathogens, thereby increasing the effectiveness of antibiotic treatment. The research is ...
Cell & Microbiology
May 22, 2026
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8
For all the diversity of the human condition, one experience is almost universally painful: adolescence. It's also unusual. Most other species pass from puberty to adulthood quickly, but humans linger for years in a transitional ...
Plants & Animals
May 22, 2026
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