Orcas off the west coast of North America are grooming each other with kelp, in a rare sighting of marine mammals manufacturing and using tools.

For several years, scientists have been keenly observing 80 endangered killer whales in the segment of the Pacific Ocean between British Columbia and Washington state. To get a bird’s eye view of the whales’ lives, the researchers also tracked them with drones.

While poring over footage from summer 2024, they noticed that the orcas were manoeuvring strands of kelp in odd ways. It was “really weird”, says at the in Washington state, “but the whales, they do weird things all the time”.

In the footage, the orcas can be spotted breaking off kelp stalks near where they meet the rock bed by grabbing them with their teeth and jerking their heads back and forth. The short, snapped-off segments were roughly equivalent in length to that of the whale’s beak-like face. Over and over again, the orcas appear to consistently target just that specific segment of the algae, not other random parts of kelp.

After breaking off a strand, a whale would then sandwich the kelp between their head and the bodies of other whales in the pod, rubbing and rolling it onto each other’s sides. They take turns cleaning each other with the kelp, sometimes grooming each other for up to 12 minutes.

“What’s cool is that they don’t have any kind of hand-like appendages, and so they’re doing all of this using very deliberate movements of their body,” says John.

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Orcas are known to rub themselves against kelp on their own, known as “kelping”. This could be a social variation of that behaviour. “We know that the social bonds in this population are super, super strong, and we know that contact is one way that they reinforce those bonds,” says John.

The behaviour was present across all ages and sexes, though the data suggests the whales that were most closely related and those closer in age were more likely to “kelp” together. Crucially, this may be a form of whale hygiene, says John, as the team found that orcas are more likely to scrub each other with kelp if they are shedding their skin.

It might still be too early to confirm whether this skincare has health benefits, says at Griffith University, Australia. He would like to see the researchers cross-reference the orcas’ skin bacteria with the properties of the kelp to see if they match.

“It totally makes sense to me that they are seeking out anything that the ocean could offer to help them with potential reduction in skin infections,” says Meynecke. He suspects this is a widespread behaviour among other orca populations and whale species.

Capuchin monkeys on a remote Panamanian island are abducting babies from howler monkey families, in a first-of-its-kind trend.

The wild population of white-faced capuchins (Cebus capucinus imitator) living on JicarĂłn Island has been monitored with 86 motion cameras since 2017 to capture their sophisticated use of stone tools to crack open hard fruits, nuts and shellfish. Five years into recording the footage, in 2022, a researcher noticed one of the young male capuchin monkeys with an infant monkey from another species clinging to its back. This capuchin, nicknamed Joker, picked up at least four baby howler monkeys (Alouatta palliata coibensis) over four months, sometimes holding onto them for more than a week.

At first, the researchers thought it was a case of “one individual who maybe is a little weird or a little quirky”, says from the Max Planck Institute of Animal Behavior, who spotted the behaviour. “We didn’t expect to find this.”

Then, five months after they saw Joker with an infant, four other young male capuchins were found carrying around howler babies. Over 15 months, the capuchin group took in 11 howler babies younger than four weeks old.

The behaviour spread around the population through social learning, like a “primate fad or fashion”, says at the University of St Andrews, UK, who wasn’t involved in the study.

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While mature female monkeys sometimes adopt abandoned babies of other species, which may be a way to practise caring for their young, the JicarĂłn monkeys doing this are all immature males. And instead of adopting abandoned infants, they seem to be actively taking the howlers from their families. There is no footage of the thefts, but they did document capuchins preventing the howler babies from escaping. Footage also shows howler monkey parents searching and calling for their infants in the canopy as the capuchins get defensive.

The abducted infants probably all die from malnourishment, since they are too young to survive without their mother’s milk. Researchers saw at least three howler monkey infants being carried around even when dead.

Learning from others can be beneficial, which is why a trend can take off even when the behaviour has no real benefits to the monkeys, says Whiten.

Since the Jicarón capuchins have no predators and very little competition, the craze could have arisen as a result of having spare time to try new things, and possibly out of boredom. There might also be something about the conditions of life on a remote island that are conducive to innovative behaviours arising and being spread. It is these same young male monkeys who most use tools on Jicarón, notes Goldsborough. “Maybe if you have a tradition already, you’re more likely to also copy their other behaviours.”

Dinosaurs likely weren’t declining before an asteroid wiped them all out; instead, there may just be limited fossils from that time period, according to a .

It has been hotly debated whether dinosaur populations were thriving or dwindling when a huge asteroid slammed into the planet about 66 million years ago. Specifically, a drop in the availability of dinosaur fossils from the years leading up to the asteroid has led some scientists to believe the giants were doomed regardless of the impact.

at University College London and his team analysed a dataset of more than 8000 fossils from four types of dinosaurs that lived between 84 million and 66 million years ago in North America, including the famed Tyrannosaurus rex and Triceratops. They found many fossils of dinosaurs from 84 million to 75 million years ago – and then that number drops in the following 9 million years leading up to the Chicxulub impact. But there was more.

When calculating how much land is currently accessible to palaeontologists from the years leading up to the asteroid’s impact and how many excavation expeditions have been undertaken in those areas, Dean’s team found there simply aren’t many of the right rocks available for today’s scientists to study.

Because palaeontologists look for fossils in ancient layers of Earth’s crust that have since been exposed to the surface, it is like working on “a puzzle where half the pieces are missing,” says Dean.

When the team used ecological models to estimate the plausible number of dinosaurs in those areas — including information about the geology and geography at the time — their calculations suggested that overall dinosaur numbers stayed stable before the asteroid impact. There weren’t fewer dinosaurs at the time; we are just less likely to find them, says Dean: “It looks like our ability to detect dinosaurs is influencing the patterns that we see in the fossil records more than anything else.”

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This adds to the growing body of research suggesting there is a bias in how many fossils palaeontologists can access from North America in the 9 million years leading up to the asteroid hit, according to from Reading University in the UK, who was not involved in the study. Yet, he says, this doesn’t change the bigger picture of dinosaurs being in decline before the asteroid hit.

Even if dinosaurs were still populous and dominant towards the end of the Cretaceous period, there doesn’t seem to be a lot of variation in their species. suggests that, during the 175 million years dinosaurs roamed Earth, the rate at which new species of dinosaurs appeared was slowing down overall, leading to more dinosaur species going extinct than new ones evolving.

This long-term decline in dinosaur diversity still holds true, says Sakamoto, despite the new research suggesting a bias in the available fossils: “Those two things are not mutually exclusive of each other.”

The science of the Jurassic Coast: Dorset and Devon, England

Join this captivating weekend getaway to the Jurassic Coast, a UNESCO World Heritage Site where the wonders of geology take centre stage.

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A species of fungus-eating orchid has an ingenious self-pollinating method. The secret lies in the orchid’s mysterious finger-like appendage.

“I knew there had to be more to it than just an odd-looking quirk,” says at Kobe University in Japan.

Suetsugu had long been fascinated by the Stigmatodactylus sikokianus orchid because it lives in shady Japanese forests and feeds on soil fungi throughout its life, rather than relying on photosynthesis. The orchid also has a little finger-like appendage under its stigma, the sticky part that receives pollen during mating.

To investigate the appendage’s purpose, Suetsugu observed the flower out in the wild, set up pollination experiments in the laboratory and tracked changes in the orchid’s flower structure with fluorescence microscopy.

He noticed that if no insects visited the orchid to pollinate it, the flower started wilting. As it drooped, the finger-like appendage gradually moved towards the stigma, bringing pollen into contact with the sticky receptor.

The appendage thus acts “like a bridge”, says Suetsugu, transferring the orchid’s pollen in a self-pollination trick, but only as a last resort. The wilting mechanism allows a plant to hold out for a pollinator but acts as a fail-safe, ensuring it can still reproduce even if an insect never arrives. The discovery “underscores how nature can come up with really creative solutions to common problems”, says Suetsugu.

The next step would be removing the appendage completely to see how much of a difference it makes in pollination timing and efficiency, says at the Australian Tropical Herbarium.

While this appears to be the first time such a self-pollinating trick has been formally documented, Nargar notes that observations from the early 1990s suggest two other closely related orchid species also use their unusual appendages to self-pollinate.

A species of hornet that often munches on foods containing alcohol can hold its liquor, without any side effects, at levels that no other known animal can tolerate.

“This is crazy,” says study author at the Ben-Gurion University of the Negev in Israel.

The diet of the oriental hornet (Vespa orientalis) consists of nectar and ripe fruits, including grapes. This fruit contains sugar that, when it naturally ferments over time, turns into ethanol.

While ethanol can be nutritious for animals, it is also highly intoxicating. Even animals that routinely eat fermenting fruits – like fruit flies and tree shrews – cannot stomach more than 4 per cent ethanol in their meals, according to Bouchebti and her colleagues.

But when Bouchebti’s team gave hornets nothing to eat for a week except a range of sugary solutions containing different quantities of ethanol – between 1 and 80 per cent – the hornets seemed to be completely unaffected. Both their behaviour and lifespan remained unchanged. What makes this particularly surprising is that the solutions with 80 per cent ethanol contain an alcohol content four times as high as anything found in nature.

“In the beginning, we did the experiment only with 20 per cent [ethanol] and we were already amazed,” says study author at Tel Aviv University in Israel. The 80 per cent ethanol figure is “even harder to believe”.

Analysis of the genomes of several hornet species suggests the insects have two to four copies of a gene that produces NADP+, which helps break down alcohol. The researchers think this might help explain why the oriental hornet – and possibly other hornet species – can handle such large quantities of alcohol.

These findings “remind us that we are not alone in our fondness for alcohol”, says at the University of Rochester in New York. But he isn’t persuaded that hornets are the only organisms that can handle this much alcohol, because data from other animal studies is hard to compare.

The hornets’ penchant for alcohol might give them a competitive edge when it comes to feeding on highly fermented foods, which are highly nutritious, says at the University of Turin in Italy. She thinks the hornets’ tolerance is probably related to the animals’ mutualistic relationship with the fermenting brewer’s yeast Saccharomyces cerevisiae, which have shown reside, survive and even mate within hornets’ intestines. Maybe the hornets help the yeasts move around from fruit to fruit, while the yeasts help the hornets find energy-rich foods.