All posts tagged: ecology

Seeds can sense the sound of falling raindrops, MIT study finds

Seeds can sense the sound of falling raindrops, MIT study finds

Published by Jenni Sidey

Rain does more than soak the ground. For some seeds, it may also act like an alarm clock. MIT engineers have found evidence that the sound of falling raindrops can speed up germination in rice seeds, apparently by physically shaking tiny gravity-sensing structures inside them. In lab experiments, seeds exposed to rain-like vibrations germinated noticeably faster than identical seeds kept in the same conditions without those sounds. The work offers what the researchers describe as the first direct evidence that plant seeds and seedlings can detect sounds in nature and use them in ways that may help them survive. “What this study is saying is that seeds can sense sound in ways that can help them survive,” said Nicholas Makris, a professor of mechanical engineering at MIT. “The energy of the rain sound is enough to accelerate a seed’s growth.” Rain sound in puddle and soil. (a) Sound pressure time series of moderate rain, roughly 0.5–3.0 mm drop diameter, in a rain puddle in a grassy field characterized by many impulsive events, measured with a …

Marine Animals in the Strait of Hormuz Don’t Get a Ceasefire

Marine Animals in the Strait of Hormuz Don’t Get a Ceasefire

Published by skeptic

As noise levels rise, whales reduce their diving activity—effectively entering a forced fasting period that weakens them over time. From Disruption to Damage In the narrow, 21-mile-wide funnel of the strait, military activity introduces shock waves and pressure changes that marine species are not built to withstand. Underwater explosions can be strong enough to kill fish outright and damage the auditory systems of larger marine mammals. Aaron Bartholomew, professor of biology, chemistry, and environmental sciences at the American University of Sharjah, suggests that “while whales and dolphins may temporarily move out of areas where there is significant naval sonar activity,” the intensity of modern maritime conflict poses lethal risks. Adam warns that the impact can be lasting: “These explosions can also damage the auditory system of cetaceans, which may temporarily or permanently lose their hearing.” Even when not immediately fatal, the effects can weaken animals over time and disrupt their ability to survive in already stressed conditions. Naval mines introduce similar risks even before detonation. When triggered, they generate high-pressure shock waves that can rupture …

A variety of jungle animals all use one type of tree as a latrine

A variety of jungle animals all use one type of tree as a latrine

Published by skeptic

A northern tamandua – a kind of anteater – using the fig tree latrine Tropical Canopy Ecology Project A host of tree mammal species, including opossums, two-toed sloths and wild cats, have been found sharing a latrine in the forest canopy. Jeremy Quirós-Navarro, an independent ecologist in Costa Rica at the time, first discovered a latrine 30 metres up a strangler fig tree while looking for somewhere flat to place a camera. He saw a natural platform, strewn with different colours and textures of faeces. Later, he noticed more latrines, always on the same species: Ficus tuerckheimii.   Quirós-Navarro and his colleagues set video traps at one latrine in the Monteverde Cloud Forest Preserve. Two months later, they were astonished to find 17 different mammal species had used it. “It was crazy,” he says. “It is almost the total number of canopy mammals that you can find in the cloud forest.” There were about three visits a day. Wildcats known as margays sprayed urine there, apparently to mark territory. Porcupines toileted and rubbed branches, leaving scent. …

How our ancestors used mushrooms to change the course of human history

How our ancestors used mushrooms to change the course of human history

Published by skeptic

Seventy-five years ago, in the depths of a peat bog in Yorkshire, UK, archaeologists made a startling discovery: the perfectly preserved remains of dozens of 11,000-year-old mushrooms. Carefully cut and intentionally scorched, it is thought that these polypores were used by nomadic Mesolithic hunter-gatherers as tinder on their travels, acting as the earliest known portable fire kit. The discovery was so unlikely because of the near-impossibility of mushrooms being preserved long enough for archaeologists to analyse them. Fungi are composed mostly of water, meaning they rapidly rot and disappear, and so are almost totally absent from the fossil record, says Hannah O’Regan at the University of Nottingham in the UK. As such, the unexpected ways that mushrooms helped our ancient ancestors survive have long remained secret, seemingly lost to time. Decades passed before we learned more. But in the past few years, new tools have finally allowed us to identify fungal DNA and micro-residues in the mouths, utensils and clothing of prehistoric humans. These breakthroughs are highlighting how a hidden fungi kingdom fed, healed and …

Top predators still prowled the seas after the biggest mass extinction

Top predators still prowled the seas after the biggest mass extinction

Published by skeptic

Artwork of a Hybodus shark, a predator that evolved in the late Permian and survived the mass extinction CHRISTIAN DARKIN/SCIENCE PHOTO LIBRARY The worst known mass extinction wiped out over 80 per cent of marine species. But despite these huge losses, many ecosystems did not collapse, with a variety of animals and even top predators managing to survive the cataclysm. The findings suggest that each ecosystem’s fate was determined, in part, by its own unique mix of species. The same may be true of modern marine ecosystems, which are also facing major threats from climate change. The end-Permian extinction struck about 252 million years ago. It seems to have been caused by massive volcanic eruptions in what is now Siberia, which led to drastic global warming, low oxygen levels in the oceans and a host of other threats. Some animal groups, such as trilobites and eurypterids (sea scorpions) were entirely wiped out; others suffered huge losses. In the aftermath, many new groups arose, including dinosaurs and ichthyosaurs. Given that so many species died out, researchers …

Cannibalism may explain why some orcas stay in family groups

Cannibalism may explain why some orcas stay in family groups

Published by skeptic

Orcas may be at risk of predation by other orcas Francois Gohie/VWPics/Alamy Biologists have seen signs of orca-on-orca predation in the North Pacific, and such cannibalism may explain why some orcas travel in large family groups. Two distinct subspecies of orcas, also called killer whales (Orcinus orca), are found in the North Pacific. Transient or Bigg’s orcas, as their name suggests, are nomadic and congregate in fluid hunting pods to hunt seals, dolphins and other whales. In contrast, resident orcas live in large groups based on maternal ties, staying with the same family their whole lives. Residents will disperse and feed on fish individually and come back together again when resting or travelling. It’s thought that the two subspecies seldom interact, but Sergey Fomin at the Pacific Institute of Geography in Russia has seen evidence of violent encounters. While strolling along the beach on Bering Island in eastern Russia, he sometimes finds the gnawed-off dorsal fins of Baird’s beaked whales and minke whales — animals that have fallen prey to voracious orcas. In the summer …

The failure of ecosystem services: Why putting a price tag on nature hasn’t worked

The failure of ecosystem services: Why putting a price tag on nature hasn’t worked

Published by skeptic

Ryan Wills for New Scientist Richard Branson, Jane Goodall and Edward Norton might seem like strange bedfellows. But in 2012, at the Earth Summit in Brazil, they stood together on stage making the case that putting a price tag on nature was the only sensible way to prevent its destruction. Goodall, who spent decades studying chimps in Tanzania, took the microphone and wavered a bit: “It’s a bit shocking to me that we have to do that. I know why we have to do that. It makes perfectly good sense… But we mustn’t forget, for the sake of our children and great-grandchildren, to keep alive that reverence for the natural world.” Her words held an ambivalence that many biologists felt towards the idea of recasting coral reefs, tundra and tropical forests in terms of dollar bills, says environmental scientist and anthropologist Daniel Suarez at Middlebury College in Vermont. But they hoped that by speaking the same language as financial markets and the boardroom executives who live by them, they could help plummeting wildlife populations to flourish. Needless …

Fossil skull discovery reveals when land animals first learned to eat plants

Fossil skull discovery reveals when land animals first learned to eat plants

Published by Jenni Sidey

Life began in the sea, and it took a long time to move onto land. Plants started creeping ashore about 475 million years ago. Roughly 100 million years later, the first backboned animals followed. For tens of millions of years, those early land animals mainly ate other animals. Now a fossil from Nova Scotia is changing that timeline. Scientists at the Field Museum in Chicago, the University of Toronto, Carleton University and the Smithsonian National Museum of Natural History report a 307-million-year-old skull from one of the earliest known land vertebrates that could handle plants. The study appears in Nature Ecology and Evolution. “This is one of the oldest known four-legged animals to eat its veggies,” says Arjan Mann, assistant curator of fossil fishes and early tetrapods at the Field Museum in Chicago and co-lead author of the study. “It shows that experimentation with herbivory goes all the way back to the earliest terrestrial tetrapods—the ancient relatives of all land vertebrates, including us.” A reconstruction of Tyrannoroter heberti, eating a fern. (CREDIT: Hannah Fredd) “The …

A North Atlantic Right Whale Baby Boom Is On—but the Species Remains at Risk

A North Atlantic Right Whale Baby Boom Is On—but the Species Remains at Risk

Published by skeptic

After nearly two decades, the baby whale came back—as a mother, with a baby of its own. Julie Albert, director of the Right Whale Sighting Network at Blue World Research Institute, a nonprofit, first laid eyes on the North Atlantic right whale known as Callosity Back in 2007 when it was still just a calf, swimming off the coast of Florida. Immediately, she says, the whale stood out. Like other North Atlantic right whales, it had callosities—patches of thick, white, rough tissue on its skin. But unlike any other known right whale, this one had those markings on its back. “That’s how she got her name,” says Albert. “She’s definitely an individual.” Then, on New Year’s Eve 2025, Callosity Back returned to Florida. A call came through from the Florida Fish and Wildlife Conservation Commission to say that an unidentified whale and her calf had been spotted off the state’s central-eastern coast. Albert describes how she and her colleagues raced to the pool deck behind a nearby beachside hotel to get a better view and …

Why did magic mushrooms evolve? We may finally have the answer

Why did magic mushrooms evolve? We may finally have the answer

Published by skeptic

Many mushroom species produce the psychoactive compound psilocybin YARphotographer/Shutters​tock Magic mushrooms have been giving humans mind-altering experiences for thousands of years, but the real reason fungi evolved these hallucinogenic chemicals may have been as a bioweapon against insects that feed on them. Psilocybin is the active ingredient in numerous species of magic mushrooms, which are found on every continent except Antarctica and have a long history of use by shamans in traditional cultures. Recently, researchers have been investigating psilocybin as a possible treatment for a range of mental health conditions from depression to post-traumatic stress disorder. The drug exerts its psychedelic effects mainly by binding to serotonin receptors in the human brain. But it has been unclear why numerous species of fungus evolved to synthesise compounds that resemble animal neurotransmitters, says Jon Ellis at the University of Plymouth in the UK. “There were suggestions that psilocybin might have a defensive role against invertebrate fungivores, but these hypotheses had never been tested,” he says. To investigate the effects of psilocybin on insects, Ellis and his colleagues …