The genomes of living animals are littered with DNA from long-gone relatives, providing a lens on evolution, past extinctions, and perhaps even solutions to agricultural problems.

The offspring of crosses between related species can sometimes fill a new environmental niche, and such hybridizations may even lead to speciation.

In the 20th century, animals such as mules and ligers that had parents of different species were considered biological flukes, but genetic sequencing is beginning to unravel the critical role of hybridization in evolution.

DNA analysis of a bizarre, 30-year-old whale skull serves as a reminder of the secrets that museum specimens keep about the natural world.

Gulf killifish have made a stunning comeback in Houston with the help of genetic mutations imported from interspecies mating with Atlantic killifish.

Specialists from the state’s Department of Fish, Wildlife and Parks are working to determine what creature a rancher shot and killed.

A study finds two species of guenon monkeys in Tanzania have been mating and producing fertile offspring for generations.

Genomic analysis reveals wolves and coyotes have hybridized, potentially complicating wolves' protection under the US Endangered Species Act.

Rick Harrison, an evolutionary biologist known for his research on speciation, has passed away at age 70.

DNA from the 40,000-year-old bones of a modern human found in Europe contains Neanderthal genes.

Full genomes of Darwin’s Galápagos finches reveal a critical gene for beak shape and three overlooked species.

Genome fusion at stem graft junctions can generate new plant species.

Species in a tightly knit genus of Old World primates have evolved tell-tale facial characteristics to prevent hybridization, a study shows.

Genetically modified Atlantic salmon, which could soon become the first transgenic animal sold as food in the U.S., can breed with wild brown trout to produce a GM hybrid.

Genomic analyses reveal that the polar bear evolved between 4 and 5 million years ago, far earlier than previous studies had estimated.

Inspired by Darwin, Mohamed Noor has uncovered the molecular dance by which a single species becomes two.

A genetic analysis reveals that the polar bear split from the brown bear some 600,000 years ago.