A lethal pulse of ultraviolet (UV) radiation may have played a role in Earth’s biggest mass extinction event, fossilized pollen grains reveal.
Pollen that dates to the time of the Permian-Triassic mass extinction event, roughly 250 million years ago, produced “sunscreen” compounds that shielded against harmful UV-B radiation, the analysis found. At that time, approximately 80% of all marine and terrestrial species died off.
For the study, which was published Jan. 6 in the journal Science Advances (opens in new tab) , a team of international scientists developed a new method of using a laser beam to examine the miniscule grains, which measure about half the width of a human hair and were found embedded onto rocks unearthed in southern Tibet, according to a statement.
Plants rely on photosynthesis to convert sunlight into energy, but they also need a mechanism to block out harmful UV-B radiation.
“As UV-B is bad for us, it’s equally as bad for plants,” Barry Lomax (opens in new tab) , the study’s co-author and a professor in plant paleobiology at the University of Nottingham in the U.K., told Live Science. “Instead of going to [the pharmacy], plants can alter their chemistry and make their own equivalent version of sunscreen compounds. Their chemical structure acts to dissipate the high-energy wavelengths of UV-B light and stops it from getting within the preserved tissues of the pollen grains.”
Related: 3.5 billion-year-old rock structures are one of the oldest signs of life on Earth
In this case, the radiation spike didn’t “kill the plants outright, but rather it slowed them down by lessening their ability to photosynthesize, which caused them to become sterile over time,” Lomax said. “You then wind up with extinction driven by a lack of sexual reproduction rather than the UV-B frying the plants instantly.”
Experts have long theorized that the Permian-Triassic extinction, classified as one of the five major extinction events on Earth, was in response to a “paleoclimate emergency” caused by the Siberian Traps eruption, a large volcanic event in what is now modern-day Siberia. The catastrophic incident forced plumes of carbon buried deep within the Earth’s interior up into the stratosphere, resulting in a global warming event that “led to a collapse in the Earth’s ozone layer,” according to the researchers.
The pollen grain used in the work. It measures about half the width of a human hair (Image credit: Liu Feng/Nanjing Institute of Geology and Paleontology )
“And when you thin out the ozone layer, that’s when you end up with more UV-Bs,” Lomax said.
In their research, the scientists also discovered a link between the burst of UV-B radiation and how it changed the chemistry of plants’ tissues, which led to “a loss of insect diversity,” Lomax said.RELATED STORIES—After the ‘Great Dying,’ life on Earth took millions of years to recover. Now, scientists know why.
—Scientists just found a hidden 6th mass extinction in Earth’s ancient past
—830 million-year-old organisms found locked in ancient crystals could be resurrected
“In this case, plant tissues became less palatable to herbivores and less digestible,” Lomax said.
Because plant leaves had less nitrogen, they were not nutritious enough for the insects that ate them. That may explain why insect populations plummeted during this extinction event.
“Often insects come out unscathed during mass extinction events, but that wasn’t the case here,” Lomax said.
Europe’s largest airline has seen annual earnings drop by 16% after cutting air fares – but revealed a price hike as it seeks to return to growth.
Ryanair reported profits after tax fell to €1.61bn (£1.35bn) for the year to 31 March, down from €1.92bn (£1.61bn) in 2024, still the second highest on record.
On average, plane tickets were 7% cheaper during this period than the 12 months before, it said.
There had been a 21% rise in fares in the year up to March 2024, which bosses had signalled was due to end.
Higher-for-longer interest rates and inflation in the first half of the year meant ticket prices had to come down, the budget carrier said.
But fares are already back on the rise, Ryanair’s chief executive Michael O’Leary said.
The airline “cautiously” expects to recover “most, but not all” of the fare decline, which he said will boost profits.
Demand for summer flights is “strong”, Mr O’Leary said, with peak fares “modestly” ahead of last year.
In recent months, that rebound has already been under way. Fares since April are on track to be “a mid-high teen per cent ahead” by the end of next month, compared with the same period last year.
That trend is expected to continue to July, August and September, Mr O’Leary said.
“While we cautiously expect to recover most, but not all of last year’s 7% fare decline, which should lead to reasonable net profit growth in 2025-26, it is far too early to provide any meaningful guidance,” he said.
“The final 2025-26 outcome remains heavily exposed to adverse external developments, including the risk of tariff wars, macro-economic shocks, conflict escalation in Ukraine and the Middle East and European air traffic control mismanagement/short staffing.”
Passenger numbers grew to a record 200 million on the back of cheaper fares, hitting a target that had been reduced due to delays in delivering new Boeing planes.
The US manufacturer has struggled with increased regulatory oversight after a door panel blew off an Alaska Airlines plane mid-flight in January last year. Strike action by staff had added to the delays.
The forecast for passenger numbers has been reduced again. Ryanair now aims to transport 206 million passengers in this financial year.
It hopes to reach 300 million passengers by 2034 and on Monday said it still expects to receive 300 new Boeing planes by 2033.
Israel has said it will allow a “basic quantity of food” into the besieged enclave of Gaza to avoid a “starvation crisis” following a near three-month blockade.
Israeli Prime Minister Benjamin Netanyahu’s office said the decision was “based on the operational need to enable the expansion of the military operation to defeat Hamas“.
Gaza, where local authorities say more than 53,000 people have died in Israel’s 19-month campaign, has been under a complete blockade on humanitarian aid since 2 March.
It comes as global food security experts warn of famine across the territory and after a UN-backed reportfrom last Monday which warned one in five people in Gazawere facing starvation.
Please use Chrome browser for a more accessible video player
3:14
Israel ramps up bombing in Gaza
The statement from the prime minister’s office said it would “allow a basic quantity of food to be brought in for the population in order to make certain that no starvation crisis develops in the Gaza Strip”.
“Such a crisis would endanger the continuation of Operation ‘Gideon’s Chariots’ to defeat Hamas,” it added.
“Israel will act to deny Hamas’s ability to take control of the distribution of humanitarian assistance in order to ensure that the assistance does not reach the Hamas terrorists.”
More on Gaza
Related Topics:
Please use Chrome browser for a more accessible video player
3:20
Gaza is ‘a slaughterhouse’ says surgeon
It comes after a British surgeon working in Gaza said in a video to Sky News the enclave is now “a slaughterhouse” amid Israeli bombardment.
Israel has just ramped up its offensive in Gaza–where it’s been conducting a military campaign in retaliation for 1,200 people killed and 251 taken hostage by Hamas on 7 October 2023 – with Palestinian health officials reporting at least 130 people were killed overnight into Sunday.
Israel Defence Forces (IDF) confirmed troops had begun “extensive ground operations throughout the northern and southern Gaza Strip”.
The Hamas-run health ministry in Gaza said 464 people had died in Israeli military strikes in the week to Sunday.
In a statement on Sunday, IDF said its air force struck “over 670 Hamas terror targets throughout the Gaza Strip to disrupt enemy preparations and support ground operations” over the past week.
Israel has launched an escalation to increase pressure on Hamas, seize territory, displace Palestinians to the south and take greater control over the distribution of aid.
This EU-UK summit has for months been openly billed by Sir Keir Starmer’s Downing Street as a hugely significant moment for this government.
The Labour leader promised in his 2024 election manifesto that the UK would sign a new security pact with the EU to strengthen cooperation and improve the UK’s trading relationship with the continent.
Since winning power in July, he has embarked on a charm offensive across European capitals in a bid to secure that better post-Brexit deal.
Monday is when the PM makes good on those promises at a historic summit at Lancaster House in London.
There, the EU and UK are expected to sign a security and defence partnership, which has taken on a new sense of urgency since the arrival of President Trump in the White House.
It is an agreement that will symbolise the post-Brexit reset, with the PM, European Commission president Ursula von der Leyen and European Council president Antonio Costa also signing off on a communique pledging deeper economic cooperation.
More on Brexit
Related Topics:
But, rather like the torturous Brexit negotiations I covered for years in London and Brussels under Conservative prime ministers, Sir Keir’s post-Brexit reset went down to the wire.
Discussions continued over night as the two sides snared up over details around fisheries, food trade and youth mobility.
It’s not that both sides did not want the reset: the war in Ukraine and the spectre of the US becoming an unreliable partner have pushed London and Brussels closer together in their common defence interest.
Spreaker
This content is provided by Spreaker, which may be using cookies and other technologies.
To show you this content, we need your permission to use cookies.
You can use the buttons below to amend your preferences to enable Spreaker cookies or to allow those cookies just once.
You can change your settings at any time via the Privacy Options.
Unfortunately we have been unable to verify if you have consented to Spreaker cookies.
To view this content you can use the button below to allow Spreaker cookies for this session only.
But the pressure for this deal weighed more heavily on our prime minister than his European colleagues. He’s been talking for months about securing a reset and better trading relationship with the EU to bolster the UK economy.
His need to demonstrate wins is why, suggests one continental source, the Europeans let talks go to the wire, with London and Brussels in a tangle over fishing rights – key demands of France and the Netherlands – and a youth mobility scheme, which is a particular focus for Berlin.
In the end, the UK allowed EU fishing boats access to British waters 12 years.
“The British came with 50 asks, we came with two – on fishing and the youth mobility scheme,” says one European source.
EU sources say Brussels had offered a time-limited deal to lift checks on animal products – replicating London’s offer on fisheries – but the UK is reluctant to do this as it leaves too much uncertainty for farmersand supermarkets.
Image: Poland’s Prime Minister Donald Tusk, Germany’s Chancellor Friedrich Merz, France’s President Emmanuel Macron and Sir Keir Starmer talk to the press after their meeting on May 16, 2025 Pic: Reuters
Scotland election weighing on talks
A deal on food products, known as sanitary and phytosanitary (SPS) goods, would be a boost for the economy, with potentially up to 80% of border checks disappearing, given the breadth of products – paint, fashion goods, leather as well as foods – with an animal component.
Any deal also means the UK would have to align with rules made in Brussels and make a financial contribution to the EU to fund work on food and animal standards.
Both elements will trigger accusations of Brexit “betrayal”, as the UK signs up as a “rule taker” and finds itself paying back into the EU for better access.
Government figures had been telling me how they are more than prepared to face down the criticisms thrown at them from the Conservatives.
But sensitivities around fishing, particularly in Scotland, where Labouris facing elections next year, weighed on talks.
The other area of huge tension was over a youth mobility scheme, which would enable young adults from member states to study and work in the UK and vice versa.
Government sources familiar with the talks acknowledge some sort of scheme will be included, but want details to be vague – I’m told it might be “an agreement about a future agreement”, while the EU sees this a one of its two core demands.
Please use Chrome browser for a more accessible video player
2:54
European leaders gather in Ukraine
In talks late on Sunday night, the UK government appeared to be softening on re-opening the pre-Brexit Erasmus student exchange scheme as perhaps a way to get around the impasse, according to one EU source.
The UK rejoining this scheme had been rebuffed by Sir Keir last year, but was raised again last night in talks, according to a source.
Common ground on defence and security
Wherever the economic horsetrading lands, the two sides have found common ground in recent months is on defenceand security, with the UK working in lockstep with European allies over Ukraine and relationships deepening in recent months as Sir Keir Starmer has worked with President Macron and others to try to smooth tensions between Kyiv and Washington and work on a European peace deal for Ukraine.
The expectation is that the two sides will sign a security partnership that will reiterate the UK’s commitment to build up the continent’s defence capability and stand united against Russian aggression with its partners.
Please use Chrome browser for a more accessible video player
3:31
Five years of Brexit explained
The deal should also mean British arms companies will be able to access the EU’s €150bn rearmament programme, which has been set up to create a massive surge in defence spending over the next five years as Europe prepares itself to better repel threats.
It is clearly in neither side’s interest for Monday to go wrong.
The EU and UK need to maintain a united front and, more importantly for Keir Starmer domestically, the PM needs to show an increasingly sceptical public he can deliver on his promises.
Easing trade barriers with Britain’s biggest trading partner and signing an EU defence pact would be two manifesto promises delivered.
And with his popularity sinking to a record low in recent days, he could really do with a win.