The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
We may be in the midst of a major human-driven extinction crisis, but it turns out that humans may have been pushing other species to the brink long before the industrial era.
A new study published in Scientific Reports Thursday found that humans played a potentially "significant" role in the extinction of the cave bear, a giant Pleistocene relative of the brown bear that could weigh as much as 2,000 pounds and went extinct around 20,000 years ago, according to The Washington Post.
The researchers used mitochondrial DNA from cave bear bones found across Europe to track the animals' population diversity and size. They found that their population stayed stable through two cooling and warming cycles before starting to decline when modern humans arrived.
"We see this dramatic drop in the population of the cave bear starting from 40,000 years ago, which coincides with the arrival of anatomically modern humans in Europe," study leader Prof. Verena Schünemann of the University of Zurich told BBC News. "It is the clearest evidence we have so far that humans might have played a big role in the extinction of the cave bear."
A debate has long raged in the scientific community over what exactly caused large mammals like cave bears, mammoths and saber-tooth cats to go extinct. Some blame the last glacial maximum 26,500 years ago, but others point to the hunting prowess of modern humans, National Geographic explained.
At least in the case of the cave bear, it appears that humans played an important role.
"If not for our arrival in Europe, I don't see any reason why cave bears should not be around today," study coauthor and University of Tübingen paleobiologist Hervé Bocherens told National Geographic.
Axel Barlow, a biologist at the University of Potsdam, Germany who was not involved with the research, told The Washington Post that the study was "very nice" and made it clear that something "quite profound happened to the global cave bear population around 40,000 years ago."
Of course, it's possible that climate change and human activity together shaped the bears' ultimate fate, Schünemann told The Washington Post. An increase in human hunting may have coincided with a decline in food, for example. And studying that interaction can help scientists understand what is happening today.
"Looking at the impact of climate change and human impact on large mammals can tell us a lot about the general process and consequences of large mammal extinction," Bocherens told The Washington Post. "Studying the past to save the future: This is what we try to do."
EcoWatch Daily Newsletter
By Emily Deanne
Shower shoes? Check. Extra-long sheets? Yep. Energy efficiency checklist? No worries — we've got you covered there. If you're one of the nation's 12.1 million full-time undergraduate college students, you no doubt have a lot to keep in mind as you head off to school. If you're reading this, climate change is probably one of them, and with one-third of students choosing to live on campus, dorm life can have a big impact on the health of our planet. In fact, the annual energy use of one typical dormitory room can generate as much greenhouse gas pollution as the tailpipe emissions of a car driven more than 156,000 miles.
By Lorraine Chow
Kokia drynarioides is a small but significant flowering tree endemic to Hawaii's dry forests. Native Hawaiians used its large, scarlet flowers to make lei. Its sap was used as dye for ropes and nets. Its bark was used medicinally to treat thrush.
States that invest heavily in renewable energy will generate billions of dollars in health benefits in the next decade instead of spending billions to take care of people getting sick from air pollution caused by burning fossil fuels, according to a new study from MIT and reported on by The Verge.
Hawaii's Kilauea volcano could be gearing up for an eruption after a pond of water was discovered inside its summit crater for the first time in recorded history, according to the AP.
By Kristin Ohlson
From where I stand inside the South Dakota cornfield I was visiting with entomologist and former USDA scientist Jonathan Lundgren, all the human-inflicted traumas to Earth seem far away. It isn't just that the corn is as high as an elephant's eye — are people singing that song again? — but that the field burgeons and buzzes and chirps with all sorts of other life, too.
Humanity faced its hottest month in at least 140 years in July, the US National Oceanic and Atmospheric Administration (NOAA) said on Thursday. The finding confirms similar analysis provided by its EU counterparts.
By Hans Nicholas Jong
Indonesia's president has made permanent a temporary moratorium on forest-clearing permits for plantations and logging.
It's a policy the government says has proven effective in curtailing deforestation, but whose apparent gains have been criticized by environmental activists as mere "propaganda."