
Aspen trees increase due to reintroduction of wolves to US national park
The reintroduction of wolves to the park in the early 1990s led to the elk population dropping sharply. The authors of the study published in Forest Ecology and Management believe this is the main reason for the resurgence of aspen trees. By looking at the particular areas where aspen trees grow over a number of years, they were able to see what had changed. Aspen trees which are also called Populus tremula, because of the way its leaves tremble, attract a wide range of wildlife.
Luke Painter ecologist at Oregon State University and lead author told the website Live Science: "Aspen are a key species for biodiversity. The canopy is more open than it is with conifers and you get filtering light that creates a habitat that supports a lot of diversity of plants."While the aspen is recovering they are not out of the woods yet. Bison also eat the young aspen shoots and numbers appear to be increasing. Overall, researchers say it shows what the effect of introducing a predator at the top of the food chain like a wolf can have on biodiversity.
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


The Guardian
4 hours ago
- The Guardian
If we're serious about protecting pregnancies, we need to stop spraying pesticides
As a biochemist trained in environmental health, I was relieved to see coverage of pesticide exposure and pregnancy risk (Exposure to a mix of pesticides raises risk of pregnancy complications, study suggests, 19 July). But one key detail is missing: food is not the main route of exposure for most women, especially in urban environments. While dietary pesticide levels are regulated, many studies – including urine biomonitoring – have shown less difference in pesticide load between children eating organic and conventional diets in cities than we would expect. Why? Because exposure is happening elsewhere. Pesticides are being sprayed by building managers, neighbours, city governments and businesses – on sidewalks, in apartment hallways, in parks, and even indoors. Many women are exposed without ever handling these chemicals themselves. In fact, a 2020 study found that urban women who used pesticides at home had the same increased risk of birth defects as women exposed to farm drift: a threefold increase in holoprosencephaly, one of the most common birth defects in the US. We must shift the conversation beyond food. These chemicals are in the air women breathe and the homes they live in – often without their knowledge or consent. If we're serious about protecting pregnancies, we need to stop the ShaveOlympia, Washington, US


BBC News
a day ago
- BBC News
Aspen trees increase due to reintroduction of wolves to US national park
For the first time in 80 years, aspen trees are thriving in Yellowstone National Park in the US, due mostly to the reintroduction of wolves to the area. According to a new study the return of wolves has led to an ecological transformation. Gray wolves disappeared from the park by 1930 because of habitat loss and hunting. Their loss led to a type of deer species, elk, taking elk chomped grass, shrubs and even young trees which meant aspen trees didn't grow. The reintroduction of wolves to the park in the early 1990s led to the elk population dropping sharply. The authors of the study published in Forest Ecology and Management believe this is the main reason for the resurgence of aspen trees. By looking at the particular areas where aspen trees grow over a number of years, they were able to see what had changed. Aspen trees which are also called Populus tremula, because of the way its leaves tremble, attract a wide range of wildlife. Luke Painter ecologist at Oregon State University and lead author told the website Live Science: "Aspen are a key species for biodiversity. The canopy is more open than it is with conifers and you get filtering light that creates a habitat that supports a lot of diversity of plants."While the aspen is recovering they are not out of the woods yet. Bison also eat the young aspen shoots and numbers appear to be increasing. Overall, researchers say it shows what the effect of introducing a predator at the top of the food chain like a wolf can have on biodiversity.


The Guardian
2 days ago
- The Guardian
Neanderthals were not ‘hypercarnivores' and feasted on maggots, scientists say
For hungry Neanderthals, there was more on the menu than wild mammals, roasted pigeon, seafood and plants. Chemical signatures in the ancient bones point to a nutritious and somewhat inevitable side dish: handfuls of fresh maggots. The theory from US researchers undermines previous thinking that Neanderthals were 'hypercarnivores' who stood at the top of the food chain with cave lions, sabre-toothed tigers and other beasts that consumed impressive quantities of meat. Rather than feasting on endless mammoth steaks, they stored their kills for months, the scientists believe, favouring the fatty parts over lean meat, and the maggots that riddled the putrefying carcasses. 'Neanderthals were not hypercarnivores, their diet was different,' said John Speth, professor emeritus of anthropology at the University of Michigan. 'It's likely maggots were a major food.' Neanderthals were thought to be top of the food chain because of the high levels of heavy nitrogen in their bones. Nitrogen builds up in living organisms when they metabolise protein in their food. A lighter form of the element, nitrogen-14, is excreted more readily than the heavier form, nitrogen-15. As a result, heavy nitrogen builds up in organisms with each step up the food chain, from plants to herbivores to carnivores. While the levels of heavy nitrogen in Neanderthal bones place them at the top of the food chain, they would not have been able to handle the amount of meat needed to reach those levels, the researchers say. 'Humans can only tolerate up to about 4 grams of protein per kilogram of body weight, whereas animals like lions can tolerate anywhere from two to four times that much protein safely,' said Speth. Since many Indigenous groups around the world routinely consume maggots in putrefied meat, the researchers decided to explore their potential role. The experiments were not for the squeamish. Dr Melanie Beasley, a member of the team at Purdue University in Indiana, was formerly at the Forensic Anthropology Center, or Body Farm, at the University of Tennessee. There, researchers study donated human corpses that are left to decompose. The work helps forensic scientists hone their techniques, for example, to ascertain for how long people have been dead. Beasley measured heavy nitrogen in putrefying muscle and the maggots that infested the corpses. Heavy nitrogen rose slightly as muscle putrefied, but was far higher in the maggots. The same process would have occurred in carcasses the Neanderthals stored, Beasley said. The finding, reported in Science Advances, suggests that rather than consuming meat as ravenously as lions and other hypercarnivores, Neanderthals acquired high levels of heavy nitrogen by eating maggots, which themselves were enriched with heavy nitrogen. 'The only reason this is surprising is that it contradicts what we westerners think of as food,' said Karen Hardy, professor of prehistoric archaeology at the University of Glasgow. 'Elsewhere in the world, a very wide range of things are eaten, and maggots are a great source of protein, fat and essential amino acids.' 'It is a no brainer for Neanderthals,' she added. 'Put out a bit of meat, leave it for a few days then go back and harvest your maggots, its a very easy way to get good nutritious food.' 'How does it shift our thinking? The Neanderthals as top carnivores was nonsense, it was physiologically impossible. So this makes sense, but also explains these high nitrogen signals in a way that nothing else has done so clearly,' Hardy said.