Climate Change Is Making It Hard for Bears to Hibernate Through the Winter

iStock
iStock

What was once a rare sight—a bear wandering outside its den before springtime—has become increasingly common, thanks to climate change. As The New York Times reports, warming temperatures are waking American black bears from hibernation earlier than ever, and in some cases, preventing them from settling down for the winter in the first place.

Hibernation is a vital part of the black bear's life cycle. When awake, a bear must consume at least 11 to 18 pounds of food per day to maintain a healthy body weight. Withdrawing for the winter allows it to survive the food scarcity that comes with the colder months.

But as climate change promotes certain extreme weather patterns in the western U.S., the region's black bear population has begun to act differently. Last year the Pine Nut Mountains in Nevada saw unusually high levels of snowfall, and the excess moisture produced an abundant pine nut crop. This past winter, snowfall in the area hit near-record lows, leaving the pine nuts exposed on the ground for a longer period. The prolonged access to food in the area meant some bears started hibernating later or just never got around to it.

Many of the bears that did eventually crawl into their dens were woken up ahead of schedule this year. According to a 2017 study, for every 1°C that minimum winter temperatures rise, bears hibernate six days fewer. In January 2018, temperatures in the Pine Nut Mountains reached 5.4°C above the 20th-century average for the region.

Some years bears emerge from hibernation during droughts, which are exacerbated by climate change, and food is hard to come by. When that's the case, bears may end up on private property, raiding people's trash cans and bird feeders and sometimes breaking into their homes. Fatal bear attacks on humans aren't common: The more likely scenario is that the so-called problem bear will be euthanized. Bear management groups will often try other strategies, like capture and release and aversive conditioning, before resorting to this option. Nonetheless, dozens of bears are euthanized by states each year.

Black bears aren't the only ursine species being forced to adapt to global warming. In the Arctic, polar bears are losing the sea ice they need to hunt marine mammals, and many of them are moving onto land in search of prey. Climate change is pushing both species of bears toward human-populated territory, which means conflicts between the bears and people will only increase from here.

[h/t The New York Times]

5 Times the Jig Was Up Because the Parrot Squawked

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iStock

Most of our feathered friends can sing, but only a few can talk. And if those talkers witness something naughty, they might just tell on you.

1. SUSPICIOUS SWEET TALKING

A woman in Kuwait, where adultery is illegal, had been suspicious for some time that her husband was carrying on an affair with their housekeeper. There were little signs, like when she returned home from work early and noticed that he seemed nervous. But it was when the family parrot squawked unfamiliar sweet nothings that she decided to take her suspicions to the police. If her husband wasn’t saying those things to her, how was the parrot learning them? However, because it could not be proven that the parrot hadn’t heard the phrases from a steamy TV show, the bird's evidence was deemed inadmissible.

2. THAT'S NOT MY NAME

In another case of infidelity revealed with a squawk, a man was surprised to hear his beloved African Grey parrot Ziggy say, “Hiya Gary!” when his live-in girlfriend’s phone rang, because his name was not Gary. After he heard the parrot say, “I love you, Gary,” and make kissing sounds when the name Gary was said on TV, he confronted his girlfriend, who admitted she was having an affair with Gary. Not only did he lose his girlfriend, but when the parrot continued to chatter on about Gary in her voice, the man was forced to give his pet up too.

3. THE AWFUL LAST LAUGH

Even when other evidence is already damning, a parrot can add an extra sinister twist to a crime investigation. When an elderly woman was found in a filthy South Carolina home, covered in bedsores and near death, her daughter was charged with elder abuse and neglect (her mother died the next day). The police noted that a parrot in the house repeatedly cried for help and then laughed. They believe it was mimicking the interaction between the mother and daughter: The mother pleading for help and the daughter laughing.

4. REPLAYING THE LAST WORDS

After a Michigan man was found shot to death in his home, his parrot kept repeating a dialogue, alternating between a man and woman’s voice, that went: “Get out.” “Where will I go?” “Don’t f***ing shoot!” His wife—who police believe tried to kill herself but did not succeed—was charged with his murder and was convicted in 2017.

5. GIVING THE CRIMINAL AWAY

Tales of parrots giving the criminal away go back to the 19th century, when the leader of a Paris crime syndicate who went by Victor Chevalier escaped with his beloved parrot from the residence he shared with his wife Marie before the cops descended on him. When an officer was called to another residence for a seemingly unrelated search, he heard as he walked in, a parrot cry out “Totor! Riri!” which happened to be the pet names of Victor and Marie. The discovery of the parrot eventually led to the capture of Victor.

This piece originally ran in 2016.

Scientists Reveal the Most Comprehensive Map of Butterfly Evolution Ever—and It's Gorgeous

Espeland et al., Current Biology (2018)
Espeland et al., Current Biology (2018)

There are 18,000 known butterfly species in the world, so maybe it’s not surprising that scientists haven’t quite worked out how they’re all related. Recently, scientists developed what is currently the most comprehensive roadmap of butterfly evolution ever, one that includes 35 times more genetic data and three times as many classifications as past butterfly evolutionary trees. Oh, and as Fast Company found, it’s beautiful.

The study, published in Current Biology, drew on genetic data from 207 butterfly species that together represent 98 percent of butterfly tribes (the classification just above genus). Led by Florida Museum of Natural History curator Akito Kawahara and Marianne Espeland of the Alexander Koenig Research Museum in Germany, the study used this genetic data and the fossil record to trace the evolution of different butterfly species and figure out when different species split off from their cousins.

A circular visualization of the butterfly family tree
Espeland et al., Current Biology (2018)

Needless to say, millions years of evolution means a lot of information to visualize in one family tree. Each bold label on the very outside of the circle represents a tribe, like Tagiadini, followed by the individual species that made it into the study, like Tagiades flesus (the clouded skipper). Species are clumped together by subgroup—in this case, Pyrginae (spread-winged skippers)—and color-coordinated by family—in this case, Hesperiidae (skippers).

The solid gray circle near the center, labeled K-PG boundary (for Cretaceous–Paleogene boundary) represents the mass extinction event that killed off most of Earth’s plant and animal species, including the dinosaurs.

A close-up of a circular visualization of the butterfly family tree
Espeland et al., Current Biology (2018)

The study confirms several pieces of information that butterfly experts had hypothesized about in previous studies, while overturning other hypotheses. Butterflies can be divided into seven different families, and though previous research estimated that the first butterflies appeared around 100 million years ago, this study pushes that date back to around 120 million years ago. But there were just a few early ancestors of butterflies prior to the mass extinction event that wiped out the dinosaurs, after which the butterfly family tree explodes into different branches.

Swallowtail butterflies (the subfamily Papilioninae, to the left in blue) were the first butterfly family to branch off, so they’re a “sister” species to all other butterfly species. Skippers (the family Hesperiidae, in purple) likely branched off next, then nocturnal butterflies like the Hedylidae family (in gray). However, some species that scientists previously thought were sister groups do not, in fact, share common ancestry, including swallowtails, birdwings, zebra swallowtails, and swordtails. The timeline shows that some butterfly species seem to have evolved together along with the plants they feed on or, in some cases, ant species with which they now have a mutually beneficial relationship.

[h/t Fast Company]

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