Female Narwhals and Beluga Whales Go Through Menopause, Too


While menopause is a fact of life for middle-aged women, it's exceedingly rare in the animal kingdom. Including humans, there are now five mammal species that experience it.

As Forbes reveals, a new study in the journal Scientific Reports finds that female narwhals and beluga whales also go through menopause as they age. Until now, only three other species—humans, killer whales, and short-finned pilot whales—were known to experience this reproductive phase and continue to live a long time afterward. 

Drawing from past research, scientists at England's Exeter and York Universities and the Center for Whale Research in the U.S. set out to discover whether menopause occurred in other marine mammal species. After examining the ovaries of 16 species of whales and dolphins, they identified narwhals and beluga whales as the only other animals that experience menopause.

Menopause refers to the period in which menstruation permanently ceases and females are no longer able to reproduce. Unlike humans and the four aforementioned whale species, most females in the animal kingdom are able to continue reproducing well into old age. This group includes elephants, which have some of the longest lifespans of any animal on Earth.

This is an oddity that has puzzled scientists for years. "For menopause to make sense in evolutionary terms, a species needs both a reason to stop reproducing and a reason to live on afterwards," one of the new study’s authors, Samuel Ellis of the University of Exeter, tells Forbes.

Previous research on killer whales (which were not included in the scope of this study) suggest that menopause is linked to grandmother whales’ relationships with their young offspring—a theory called the “grandmother hypothesis.” Ellis notes that “both male and female [killer whale] offspring stay with their mothers for life—so as a female ages, her group contains more and more of her children and grandchildren.”

The whale’s children and grandchildren are all competing for resources such as food, so that may be why menopause steps in to shut down her reproductive cycle. It's believed that grandmother whales continue to live on well after menopause—unlike other species that go through something like menopause, but die shortly after—because they provide crucial knowledge to their close-knit groups of descendants. The authors of the latest study say there is also evidence that our human ancestors followed similar social patterns.

[h/t Forbes]

A Python Swallowed a Crocodile Whole—and a Photographer Was There to Capture It All

KarenHBlack/iStock via Getty Images
KarenHBlack/iStock via Getty Images

As long as it can fit through their elastic jaws, there's not much pythons won't eat. This genus of snakes has been known to swallow everything from small bears to porcupines. As Live Science reports, a python was recently spotted eating a crocodile in Australia—and the disturbing encounter was caught on camera.

On May 31, 2019, the Australian nonprofit GG Wildlife Rescue Inc. shared photos a kayaker named Martin Muller captured of a snake inhaling a crocodile outside Mount Isa in Queensland. The snake was an olive python—a native Australian species that's found exclusively on the continent. Pythons can subdue large prey by wrapping their powerful bodies around it and constricting the animal until it suffocates. Killing a large, aggressive predator like a freshwater crocodile is only half the job. Once its prey is ready to eat, the python opens its jaw, which can stretch several times larger than its head, and gradually consumes its meal, a process that can take hours.

The images below offer a rare look at this brutal act of nature. Muller captured the entire scene, from the python wrangling the croc to the gluttonous feeding that takes place afterwards. The last photos in the series show the python with a large, lumpy bulge in its belly—a sign of its success.

Pythons have been spotted eating crocodiles and alligators in the past, and it doesn't always end well for them. In 2005, a Burmese python in Florida—where they're an invasive species—burst open after trying to swallow an alligator whole. If this python spotted in Australia can stomach its meal, the croc will potentially sustain the snake for months.

[h/t Live Science]

An Underpass for Turtles in Wisconsin Is Saving Dozens of the Little Guys’ Lives

Dmytro Varavin/iStock via Getty Images
Dmytro Varavin/iStock via Getty Images

Why did the turtle cross the road? Because an underground tunnel made it safe to do so.

In 2016, the Wisconsin Departments of Transportation and Natural Resources partnered with the University of Wisconsin-Stevens Point to construct a tunnel beneath Highway 66, hoping to cut down on high turtle mortality rates, reports Robert Mentzer for Wisconsin Public Radio.

The tunnel, with Jordan Pond on one side and wetlands on the other, was a noble venture, but the turtles had no way of knowing it was a crossing point rather than a dark and potentially dangerous hole. So Pete Zani, herpetologist and associate professor of biology at the University of Wisconsin-Stevens Point, installed aluminum flashing outside of each opening, which would reflect the sky and let turtles know that there’s a light at the end of the tunnel. Zani also installed grates above the tunnel to make it less shadowy, and a small cul-de-sac in a nearby piece of the fencing to encourage turtles who had missed the tunnel to turn around.

Zani and his team found that in the first year after construction, 85 percent fewer turtles were killed on the road, and no baby turtles were among the casualties. In the last few years combined, only 40 turtles died, compared to 66 deaths in 2015 alone.

That’s great news for local turtles, of course, and it’s great news for local humans, too. The intersection in question is always busy with truckers, commuters, and families en route to Jordan Pond, and turtle crossing can exacerbate traffic congestion and increase the chance of accidents.

Not all turtles have caught on, however, and it looks like some might never get the memo. Zani found that about 30 percent of snapping turtles and 20 percent of painted turtles make it through the tunnel, and those numbers have been consistent each year since construction. “They either get it or they don’t,” Zani told Wisconsin Public Radio.

Other animals are getting it, too. As part of the experiment, Zani set up a turtle-wrangling program in which students monitored trail cameras for turtle activity outside the underpass. In photos captured by the cameras, they noticed that rodents, mink, skunks, raccoons, and even house cats were traveling by turtle tunnel.

[h/t Wisconsin Public Radio]