The Saturday briefing

KNOWLEDGE IS POWER

- by CAROLINE FORD

Is there anything you're yearning to know? Send your questions, on any subject, to the contacts given below, and we will do our best to answer them...

If the dinosaurs had not died out, what possible effect would that have had on the development of Homo sapiens?

Chris Evans, Maidstone, Kent

When an asteroid struck the earth 66 million years ago, only the small, feathered flying dinosaurs we know today as birds made it through. The extinction cleared the evolutionary stage for mammals - creating the lineage that would lead to humans.

The mammals that survived - mostly small, nocturnal, burrowing creatures - were able to rapidly diversify in size and form.

Had the dinosaurs not been wiped out, palaeontologists have proposed they would have continued to evolve and rule the planet, as they'd already survived rising and falling seas, temperature fluctuations and volcanic eruptions for more than 160 million years.

Dinosaurs occupied most of the ecological niches when the asteroid hit and large mammals - such as mammoths and rhino - would probably never have had the chance to become the dominant land animals.

Scientists speculate that the evolution of primates and ancestors of Homo sapiens - from small, tree-dwelling mammals in the late Cretaceous period - would likely also not have occurred.