Ancestor [noun]

An analysis of molecular alterations in mitochondrial DNA samples indicated that two maternal lineages had split from a common ancestor between about 86,000 and 22,000 years ago.

Eventually alien biologists in these places might concern themselves with a tree of life incorporating multiple planetary incubators, and their genome-mapping companies would tell you who your planetary ancestors were.

None of the matings in any of the generations are between individuals with a common ancestor.

While BigDog is the ancestor of later four-legged robots, like Spot, Petman preceded the two-legged Atlas robot.

Proof that the handedness of particles really can mutate microbes would strengthen their case that cosmic rays shoved our ancestors off the evolutionary starting block, but it still wouldn’t fully explain the uniform chirality of life on Earth.

The team also analyzed another egg, found in Argentina and dating to between 209 million and 227 million years ago, attributed to Mussaurus, a sauropod ancestor.

Fossil tracks preserved in a South Korean rock formation are the first footprint evidence that some ancient ancestors of modern crocodiles walked on two legs.

They come from a common ancestor, and have taken strikingly similar forms even though they have evolved on different continents.

Some of these were ancestors of Tyrannosaurus rex, which didn’t live during the Jurassic.

For thousands and thousands of years, our ancestors worried about not getting enough food to eat, and their daily life required physical activity.