This seems like a minor concern, after coral bleaching and mass extinction, but it can have serious effects. Take the salmon example: Smaller fish means less money for the communities that rely on catching them. It means less food for the wolves and bears to eat them. It means they produce proportionally fewer eggs, which plays an important role in replenishing the rivers when the salmon return there to spawn. Sarah Sanderson, lead author of the paper and PhD candidate in biology at McGill.
Trait changes can have a similar effect. One year 2021 research in Mozambique’s Gorongosa National Park shows that the proportion of female elephants born without tusks has increased to more than 50%, as extreme levels of poaching during the 15-year civil war have made the strongest elephant on the head vulnerable. exist. Tuskless elephants are more likely to pass on their genes to the next generation. Elephants without tusks won’t shape the ecosystem in the same way as their cousins: They won’t tear the ground, for example, when digging for tubers. And analysis of the DNA in their droppings shows that the tusks don’t eat different types of plants.
To compare changes between species over time, the researchers used metrics known as darwins and haldanes (after British scientist JBS Haldane). These are statistical measures that provide a way to compare different types of information in the database — from the height of birch trees growing near smelting facilities in Russia to the acidification of lakes in Russia. How Sweden is affecting frog survival rates.
The new analysis shows a higher rate of phenotypic change in populations affected by human activity than in unaffected populations. But the researchers were surprised to find so little evidence that climate change was the cause of the phenotypic change. Pollution appears to be a much larger driver, responsible for changes like those observed in Russian and Swedish lakes. “We think it’s because it’s hard to say what [caused by] Hendry said. “Climate change is happening everywhere.”
The effects of climate change won’t be felt equally around the world: In the Arctic, that could mean polar bears developing new predatory behaviors that don’t rely on ice; in the ocean, which means that coral strains have adapted to living in stressful environments become the dominant species, replacing the ones we know. “Many of them are growing very quickly in response to these changes,” says Sanderson. “But what you don’t see and what we can’t really quantify [with this work] is that all these populations are not adapted, and are on the verge of extinction. “
Proceed database is available Online for academia hoping to answer new questions about rapid evolution. It now asserts that human action is altering plant and animal species in ways they may never recover — the natural world forever marked by pollution, and hopefully Man’s only desire to hunt and harvest has long surpassed individual satiety.
That may seem difficult, but you can also interpret these results with peace of mind. If we’re overfishing to the point where species start to shrink, then perhaps it’s just a sign that humans aren’t immune to the feedback loops that govern every other living thing. The animals we know will change or disappear, and new ones will evolve to take their place — life will last, even if life as we know it isn’t. “Because of studies like this, I’m not afraid of life on Earth under climate change,” said Thomas Cameron, a senior lecturer in animal ecology at the University of Essex, who was not involved in the study. . “The natural world will still exist, but it may not be the old world and some species will become extinct. But others will change and evolve.”
