Females prefer city frogs' tunes

Date:  December 10, 2018

Source:  University of Texas at Austin

Urban sophistication has real sex appeal -- at least if you're a Central American amphibian. Male frogs in cities are more attractive to females than their forest-frog counterparts, according to a new study published in Nature Ecology and Evolution.

Frogs in urban areas have more conspicuous and complex vocal calls, in part because they have fewer predators than those in natural habitats, say scientists from Vrije Universiteit (VU) in the Netherlands, The University of Texas at Austin, Purdue University and the Smithsonian Tropical Research Institute in Panama.

University of Texas at Austin professor of integrative biology Mike Ryan joined team leader Wouter Halfwerk and colleagues to investigate how city life has altered the signaling behavior of male túngara frogs. The trappings of cities often interfere with animal communication, as noise and light pollution affect the visual and auditory signals animals use to attract mates. Halfwerk previously has published work showing how urbanization affects birdsong in Europe.

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Half-Size, Ruffle-Headed Relative of Triceratops Discovered

By Laura Geggel, Senior Writer | December 14, 2018 11:20am ET

If head frills were a fashion statement, a newly identified 73-million-year-old triceratops relative was certainly at the top of its game.

The newfound dinosaur named Crittendenceratops krzyzanowskii sported a fancy frill on the top of its head, a new study finds. In fact, it's the youngest-known dinosaur of its clade (the nasutoceratopsins), as well as the first of its clade on record to sport an elaborate frill, the researchers said.

"This clade has simple frills." said study co-lead researcher Sebastian Dalman, who was at the New Mexico Museum of Natural History and Science at the time of the research. "Crittendenceratops is the first member of this clade with [an] ornamented frill." [Tiny & Old: Images of 'Triceratops' Ancestors]

The late Stan Krzyzanowski, a research associate at the New Mexico Museum of Natural History and Science, discovered two of the late Cretaceous creatures in the 1990s in a mountain range near Tucson, Arizona. Krzyzanowski and his colleagues briefly described the dinosaur in a 2003 study, but it wasn't until recently that another look at the fossils revealed they represented an unidentified species.

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Unpredictable food sources drive some bats to cooperatively search for food

Date:  December 13, 2018

Source:  University of Maryland

Humans aren't the only species that have dinner parties. Scientists have observed many animals, including bats, eating in groups. However, little was known about whether bats actively help each other find food, a process known as social foraging.

With the help of novel miniature sensors, an international group of biologists that included University of Maryland Biology Professor Gerald Wilkinson found that bat species foraged socially if their food sources were in unpredictable locations, such as insect swarms or fish schools. In contrast, bats with food sources at fixed locations foraged on their own and did not communicate with one another while foraging or eating. The results of the study were published in the November 19, 2018 issue of the journal Current Biology.

"We were able to show that bats who can't predict where their food will be are the ones that cooperate with each other to forage," Wilkinson said. "And I don't think they are unique -- I think that if more studies are done, we will find that other bat species do similar things."

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Think Keeping Up With Your Dog Is Tough? Try a Pet Tortoise - via Herp Digest

The hardy reptiles are escape artists, capable of evading enclosures and law enforcement; ‘I put on my lights. He kept going’ 

By Kathleen Hughes, Wall Street Journal, 12/11/18 

Biz Stone, the co-founder of Twitter, discovered last March that the family’s pet Russian tortoise, Roshi, had escaped from their yard in Marin County, Calif. 

Mr. Stone’s wife, Livia, had put Roshi on the grass under a mesh tent to protect him from their new Black Labrador puppy while she moved their chickens out of the coop. 

“In those five minutes,” says Mr. Stone, “Roshi managed to dig out, boogie to the edge of the property, and get under the fence. 

The couple needed to break the news to their 6-year-old son, Jake. “Let’s not freak out,” suggested Ms. Stone, as they searched in vain for the rescue tortoise they had kept for 15 years. “Let’s say Roshi went on a grand adventure.”

Eight months later, Jake, now 7, was in a gardening class in school, not far from the house, when someone said, “Oh look, a tortoise!” 

It was Roshi, eating the clover. “That’s my tortoise!” said Jake, who spotted the familiar three white splotches on his shell. “Incredible!” tweeted Mr. Stone in October. “Roshi is back after a grand adventure.”

 Aesop’s fable, it seems, may have sold the tortoise short. Tortoises and turtles of all types have soared in popularity as pets. It turns out they are resilient escape artists with long lives—and surprisingly adept at outmaneuvering their owners.

“Tortoises can walk really fast and get really far away,” says Susan Tellem, executive director at American Tortoise Rescue in Malibu, Calif. “They have nothing to do all day but figure out how to escape.”

Tortoises have been breaking out of fenced yards, heading down sidewalks and crossing busy streets at a good clip—leaving heartbroken owners and bewildered bystanders to post lost and found photos on social media.

Speeds vary by tortoise, experts say, but one British tortoise, Bertie, was clocked at a pace of .92 feet per second, which made him the Guinness World Record holder as fastest tortoise. 

Many owners never research the challenge of building a truly secure outdoor habitat. “Tortoises can scale a 6-foot fence and dig a 20-foot burrow,” warns James Liu, managing director of the Turtle Conservancy in New York. A tortoise on the run could be seeking a mate, heading out to lay eggs or foraging for food, he adds. 

There could be as many as a million pet tortoises in California, according to the Tortoise Group, a Las Vegas nonprofit focused on the welfare of the desert tortoise. The group estimates there are more than 188,000 tortoises in captivity in the greater Las Vegas area alone. That rivals the number of wild tortoises roaming free in the Mojave Desert, says Kobbe Shaw, the executive director of the Tortoise Group, which sponsored a study on captive tortoises. 

Those who start with a cute little baby tortoise from a pet store, particularly if it is an expensive Sulcata, are often shocked as it grows to more than 100 pounds. And many tortoises have lifespans of well over 60 years. While some may break free, others are eventually dumped. Some are stolen. 

“We get 1,500 calls a year about abandoned tortoises,” says Mr. Shaw who drives around Las Vegas picking up lost and found tortoises in his gray Honda Accord, with an odometer that has passed 250,000 miles. 

The escapees are considered a threat since pet tortoises can carry diseases that can wipe out vulnerable wild tortoises.

Consider Tortle, a 50-pound pet Sulcata tortoise the size of two basketballs. 

Three years ago, Ronna Rodarte, who works with special-needs children in Lancaster, Calif., came home to find traffic stopped in both directions. Tortle had exited her front yard, probably through an open gate, making it to the center yellow line of the boulevar

“The traffic travels at 70 miles per hour,” she says. “It was wonderful to see how many people stopped.” Ms. Rodarte put a padlock on the gate. This year, the day after Thanksgiving, Tortle went missing again. He failed to show up for meals, and Ms. Rodarte searched his burrow, which curves out of sight.

“I’m 200 pounds and I almost made it into the burrow,” says Ms. Rodarte. But since she didn’t fit, she rigged a mirror to a curtain rod and dropped a flashlight down using a dog leash. The burrow was empty. 

After days of searching, the family finally spotted Tortle. He had scaled a tall display case in the yard, becoming wedged between a chain-link fence and a heap of furniture and appliances covered with a tarp. 

Ms. Rodarte is considering finding Tortle a safer home, fearing that her family members don’t take his security seriously. “No one loves that tortoise like I love him. 

Last month, Alicia Chavez, a medical assistant in Peoria, Arizona, went to work, leaving Bubba, her 40-pound Sulcata tortoise in the front yard. Her brother-in-law called at 5 p.m. to say the gate was open. Bubba was gone. 

“When we called his name and he didn’t show up, we knew something was wrong,” says Ms. Chavez. “We were panicked.” The family put up fliers and searched the neighborhood. 

Ms. Chavez posted Bubba’s photo on the Tortoise & Turtle Lost & Found page of Facebook . Ten minutes later, Peoria Police Animal Control officer Megan Smith called to say she caught Bubba after he was spotted crossing the street near City Hall. 

“I could see his little bottom tail walking,” the officer says. “I put on my lights. He kept going. He was heading to the alley.”

Ms. Smith stopped her truck and got out. ”I ran and grabbed him,” she says. “He was unusually fast for a tortoise.” 

The family retrieved Bubba at the police station.

“I don’t think he would have come back on his own,” says Ms. Chavez. “Bubba just likes to be on the go.” 

Last week, Ms. Chavez tried to create a more secure area for Bubba by placing cinder blocks around a doghouse.

Researchers observe a defense mechanism for caterpillars can attract unwanted attention

December 17, 2018, Ecological Society of America

When a caterpillar disguises itself as a snake to ward off potential predators, it should probably expect to be treated like one.

This is exactly what happened in Costa Rica earlier this year, when researchers witnessed a hummingbird defending its nest from what it interpreted to be a snake, but was actually a larva of the moth Oxytenis modestia. The encounter is described in a new paper published in the Ecological Society of America's journal Ecology.

These moths—sometimes called the dead-leaf moth or the Costa Rica leaf moth—resemble flat dried leaves as adults. The caterpillars can inflate the top of their heads to expose a pair of eyespots. When disturbed, they raise their head up and move from side to side, increasing the snake-like appearance. In particular they resemble a green parrot snake, known to prey on nesting birds.

The attacking hummingbird's nest with eggs was about 10cm away from the caterpillar in a small tree. When the researchers went to look for an assumed snake, they instead found the caterpillar feeding on a leaf immediately above the nest.

"Hummingbirds have a few stereotypical styles of flying: visiting flowers, preying on swarms of tiny insects, chasing each other, and mating/territorial display flights," says lead author James H. Marden, professor with the Department of Biology at Pennsylvania State University. "Mobbing behavior directed against a threat to their nest is much less common but distinct and easy to recognize if you know their other flight behaviors... One can recognize this from a distance and only notice the source of their agitation upon close inspection."

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