A wide variety of fruits and seeds that were smothered in the ash from a volcanic eruption nearly 75 million years ago suggest flowering plants were diverse and thriving in the time of the dinosaurs, far earlier than previously known.

Researchers had thought the emergence of large seeds and fruits followed the end-Cretaceous extinction, 66 million years ago, and was tied to the rise of mammals and birds.

“Now, we have evidence that large fruit and seeds and the related ecological conditions can be traced back to 10 million years before the asteroid impact that wiped out the dinosaurs,” says at the University of California, Berkeley.

Lee and his colleagues analysed ancient fossils collected from the Jose Creek Formation in New Mexico over the past three decades. They are so well preserved because, like the Roman city of Pompeii, the plant fossils were locked within a bed of ash from a volcanic eruption.

The team discovered an extraordinary 77 different kinds of fruits and seeds. Such a ready banquet of nutritious fruit would almost certainly have been eaten by herbivorous dinosaurs and other animals.

The findings show flowering plants that enclose their seeds in fruit, also known as angiosperms, were co-evolving with the animals that fed on them as a way of dispersing their seeds.

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“While many Mesozoic animals, like dinosaurs, birds, pterosaurs and mammals, were suggested to have consumed angiosperm diaspores, we didn’t have the botanical evidence supporting this,” says Lee. “Now we have.”

The first flowering plants emerge in the fossil record 136 million years ago, but, until now, it was thought early forms were mostly small and weedy and vastly different to the range of species that dominate Earth’s forests today.

In Cretaceous deposits elsewhere, the fruit and seeds are roughly the size of a poppy seed on average – far smaller than the blueberry-sized seeds at Jose Creek.

Of the 77 new types of seeds identified by the scientists, nearly a third are classified as fleshy while only 5 per cent are winged, which would imply dispersal by wind rather than animals.

Alongside the flowering plants, the tropical forest also contained several kinds of conifers, including a redwood relative, as well as palms.

While many of the seed shapes are familiar to us today, the forest structure would have been extremely different and unfamiliar, says team member , also at the University of California, Berkeley.

The larger fossils can be compared to blueberries and large acorns in size, she says. “We don’t have a good idea which plant group produced these; for that, you have to find them attached to shoots with leaves,” says Looy. “However, when they are fleshy they are likely dispersed by larger herbivores.”

On 4 March 2022, astronauts locked 20,000 moss spores outside the International Space Station and left them exposed to the rigours of space for 283 days. They then rescued the spores and returned them to Earth on a SpaceX capsule so that scientists could attempt to germinate them. Surprisingly, these attempts were successful.

Mosses were among the earliest land plants and are well known for colonising some of the harshest environments on Earth – Antarctica, volcanic fields and deserts, says at Hokkaido University in Japan, who was on the team that ran the experiment.

“We wondered whether their spores might also survive exposure to outer space – one of the most extreme environments imaginable,” he says.

Numerous studies have already simulated whether various mosses and other plants can survive conditions beyond Earth, including what might be expected on Mars. But this is the first time researchers have tested whether a species of moss can cope with real space conditions. The spores came from the species Physcomitrium patens.

A control group of spores that had stayed on Earth had a germination rate of 97 per cent, as did another set of spores that were exposed to space but shielded from the damaging ultraviolet radiation found there.

Most astonishingly, over 80 per cent of the spores that were exposed to the full brunt of space – a vacuum, extreme temperatures, microgravity, UV and cosmic radiation – remained viable and germinated into normal plants. The team predicted it is possible that, based on the results of these experiments, some of the spores could remain viable in space for 15 years.

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“Opening the samples felt like unlocking a biological time capsule: life that had endured the void of space and returned fully functional,” says Fujita.

Prior to the deployment, researchers had already tested other living parts of the moss, such as its filaments, in simulated conditions. They found that other life stages of the moss succumbed to UV radiation, freezing and heating, high salinity and dehydration within days to weeks.

But the spores seemed to be able to cope with all of these challenges. This is especially impressive for the spores that were locked outside the space station, since they were hit with everything at once while the Earth-based tests each involved testing just one stressor at a time.

Fujita says the multiple layers of spore walls that encase the reproductive tissue appear to offer “passive shielding against space stresses”.

He says it is as if the spores are inside their own spacecraft. This might have been an adaptive feature they developed to cope with the harsh environmental conditions that existed on land when life first moved out of the oceans hundreds of millions of years ago.

“Spores are essentially compact life capsules – dormant but ready to reactivate when conditions become favourable,” he says. “It’s as though evolution equipped them with their own tiny survival pods, built for dispersal across both space and time.”

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Fujita says that while the research doesn’t in any way prove that extraterrestrial life exists, it strengthens the case that life, once it has emerged, can be incredibly robust. “The fact that terrestrial life forms can endure space-like conditions suggests that life’s building blocks may be more widespread and persistent than we often assume.”

at the University of New South Wales in Sydney says the true test isn’t whether the spores will germinate once back on Earth, but whether they can also germinate in space.

“The trick will be to check the growth rates of these taxa in space and see whether they can reproduce,” he says.