Wild Lizards Care What You're Wearing

Bad news, pals: Your mom isn't the only one judging your outfit. A recent study published in the journal PLOS One finds that wild animals—in this case, lizards—respond differently to humans depending on the color of their clothes.

It makes perfect sense, if you think about it. Animals rely on their color vision to find food, evade predators, and seduce their mates. From a survival standpoint, color is information, no matter who's wearing it.

Previous studies have found that some bird species with orange or red feathers are less afraid of people wearing orange and red. Would other brightly colored animals have a similar response?

To find out, evolutionary biologist Breanna Putman considered a lizard. The western fence lizard makes its home in the desert climes of the western United States. Both sexes are brown or black, but the males have vibrant blue patches on their bellies and throats, and some have shiny blue spots on their backs. When challenged, males do little push-ups to flex their blue scales and make them look even more impressive. Blue, then, was the color to beat.

Putnam headed out to two lizard hotspots, one at a public park in Los Angeles and another at a nearby nature reserve. The bird studies had only compared people wearing orange and red with people wearing dark gray, which means it's possible that the birds would have responded well to any bright color. So Putnam brought along four t-shirts: one each in dark blue, light blue, bright red, and gray. The dark blue shirt was a pretty close match to the color of the male lizards' macho patches.

For each trial, Putnam put on a shirt, then tried to approach a lizard. At first, she merely walked casually toward them. After a few weeks of this, she switched and began trying to catch them. For every approach, she measured how close the lizard let her get, and how quickly and how far it ran away.

Sure enough, the dark-blue shirt seemed to put the lizards at ease, or at least more at ease than the rest of her wardrobe. While Putnam wore their favorite color, the lizards let her get twice as close (39 inches vs. 78 inches) than they did with other colors. They also didn't try very hard to escape. In red, light blue, or gray, Putnam caught her quarry 40 percent of the time. In dark blue, that number went up to 84 percent.

The findings are a good reminder to all animal researchers, Putnam said in a statement. "What we wear can have indirect effects on animals through changes in their behavior."

Middle School Student Discovers Megalodon Tooth Fossil on Spring Break

iStock.com/Mark Kostich
iStock.com/Mark Kostich

A few million years ago, the megalodon was the most formidable shark in the sea, with jaws spanning up to 11 feet wide and a stronger bite than a T. Rex. Today the only things left of the supersized sharks are fossils, and a middle school student recently discovered one on a trip to the beach, WECT reports.

Avery Fauth was spending spring break with her family at North Topsail Beach in North Carolina when she noticed something buried in the sand. She dug it up and uncovered a shark tooth the length of her palm. She immediately knew she had found something special, and screamed to get her family's attention.

Her father recognized the megalodon tooth: He had been searching for one for 25 years and had even taught his three daughters to scour the sand for shark teeth whenever they went to the beach. Avery and her sisters found a few more shark teeth that day from great whites, but her megalodon fossil was by far the most impressive treasure from the outing.

Megalodons dominated seas for 20 million years before suddenly dying out 3 million years ago. They grew between 43 and 82 feet long and had teeth that were up to 7.5 inches long—over twice the size of a great white's teeth. They're thought to be the largest sharks that ever lived.

Megalodon teeth have been discovered on every continent except Antarctica, but they're still a rare find. Avery Fauth plans to keep her fossil in a special box at home.

[h/t WECT]

Watch the Denver Zoo’s New Baby Sloth Cuddle Up With Its Mom

Denver Zoo
Denver Zoo

If you’re a sucker for itty, bitty, furry animals, then you’ll want to drop whatever it is you’re doing and check out this video of the Denver Zoo’s newest resident. Uploaded by The Denver Post, the video shows a week-old sloth clinging to its mother, and it’s almost too cute to handle.

The healthy baby, whose name and sex have not yet been determined, was born on April 11 to its proud sloth parents: 23-year-old Charlotte Greenie and 28-year-old Elliot. It also has an older sister, named Baby Ruth, who was born in January of last year. Dad and Baby Ruth are “temporarily off-exhibit” to give mom and her newborn baby the chance to rest and bond in their habitat—an indoor aviary that's part of the zoo's Bird World exhibit.

The baby belongs to one of six species of sloth called the Linne's two-toed sloth, which is native to the rainforests of South America and are not currently considered threatened. Unlike their distant relatives the three-toed sloths, two-toed sloths are mostly nocturnal creatures. They also tend to move faster than their three-clawed counterparts, although fast is putting it generously.

Like many things sloths do, the baby was slow to arrive. Zoo officials predicted that Charlotte would give birth as early as January, but the expected due date may have been a miscalculation.

“Sloth due dates are notoriously challenging to predict because sloths are primarily active at night and we rarely observe their breeding,” the zoo said in a statement. “Our animal care team closely monitored Charlotte for months to ensure that she and the baby were healthy and gaining the appropriate amount of weight.”

The baby is expected to cling to its mother for at least six months. Zoo officials say the best time to visit mom and baby is in the late afternoon, when Charlotte is more likely to be active.

[h/t The Denver Post]

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