Research for first time suggests tendon and bones in heavier species would have made bounding possible

Giant 250kg kangaroos that once roamed Australia would probably have been able to hop despite their enormous size, researchers have said.

While modern kangaroos are known for their ability to travel large distances by jumping with both hind legs at the same time, it has long been debated whether their extinct relatives would have been so springy.

OpenAI, Anthropic, SpaceX and Stripe are rumoured to be among ten of the biggest companies considering IPOs

You’ve probably heard of “unicorns” – technology startups valued at more than $1bn – but 2026 is shaping up to be the year of the “hectocorn”, with several US and European companies potentially floating on stock markets at valuations over $100bn (£75bn).

OpenAI, Anthropic, SpaceX and Stripe are among the big names said to be considering an initial public offering (IPO) this year.

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Archaeologists say stencil painted with ochre in limestone cave on Muna Island was created at least 67,800 years ago

The faded outline of a hand on a cave wall in Indonesia may be the world’s oldest known rock art, according to archaeologists who say it was created at least 67,800 years ago.

The ancient hand stencil was discovered in a limestone cave popular with tourists on Muna Island, part of south-eastern Sulawesi, where it had gone unnoticed between more recent paintings of animals and other figures.

Veronika’s improvised grooming device has caused great surprise – but that tells us more about humans than cows

I have a farmer friend who regularly regales me with colourful stories of her cattle. Take the time when a beef cow called Noisette used her tongue to pull back the catch on the door of her pen so she could steal cattle nuts from the nearby feed bin. Or the time when she did it again, not to let herself out, but seemingly to stand back and watch as her freed compatriots “mooched around and caused mayhem.”

Where others see a herd of cows standing around looking bored, my friend sees a soap opera, with characters and plot twists. Cows, she tells me, learn quickly, bore easily and have an indefatigable penchant for mischief.

Helen Pilcher is a science writer and the author of Bring Back the King: The New Science of De-Extinction