NEWS AND NOTES ABOUT SCIENCE
BETWEEN A T. REX’S POWERFUL JAWS, BONES OF ITS PREY EXPLODED
It’s no surprise that the Tyrannosaurus rex had a mighty bite, but just how powerful were its gigantic chompers? A study published May 17 suggests that the terrifying carnivore crushed its prey with a jaw-dropping 7,800 pounds of force — more than double what any living species can deliver.
“That’s equivalent to putting three small cars on top of the jaws — that’s what’s pushing down on you,” said Gregory M. Erickson, a paleobiologist from Florida State University and co-author of the study that appeared in the journal Scientific Reports. “Boom! It’ll puncture through just about whatever’s in there.”
Even bone, according to Erickson. The finding helps provide more evidence to the idea that the T. rex shattered bones and swallowed the fragments for sustenance. The behavior, known as extreme osteophagy, is seen today in carnivorous mammals like gray wolves and spotted hyenas, but not in reptiles.
“If you could bite through bone, you can get nutrients from within the bone itself,” said Paul M. Gignac, a paleobiologist at Oklahoma State University and the lead author on the paper.
This strategy of crushing and ingesting bones would have been particularly useful for the T. rex,
according to the researchers, because the giant dinosaur was not only an efficient killing machine, but also an opportunistic scavenger. If a T. rex came across a carcass, it could still enjoy an easy meal.
Erickson became curious with figuring out the bite force of the T. rex as a graduate student in the mid-1990s when a colleague showed him a fossilized triceratops pelvis riddled with about 80 bite marks.
“I remember saying to him, ‘Gosh, it looks like Clifford the Big Red Dog chewed it up,’” Erickson said. Nicholas St. Fleur
LADYBUGS PACK WINGS AND ENGINEERING SECRETS IN TIDY ORIGAMI PACKAGES
The ladybug is a tiny insect with hind wings four times its size. Like an origami master, it folds them up into a neat package, tucking them away within a slender sliver of space between its abdomen and the usually polka-dotted, harder wings that protect it. When it is time to take off, it deploys its flying apparatus from beneath its colorful shell-like top wings, called the elytra, in only onetenth of a second. And when it lands, it folds it back in just two. Switching between flying and crawling many times in a day, the ladybug travels vast distances.
To the naked eye, this elegant transformation is a mystery. But scientists in Japan created a window into the process in a study published May 15 in Proceedings of the National Academy of Sciences. Just how the ladybug manages to cram these rigid structures into tiny spaces is a valuable lesson for engineers designing deployable structures like umbrellas and satellites.
A ladybug’s hind wings are sturdy enough to keep it in the air for up to two hours and enable it to reach speeds up to 37 mph and altitudes as high as three vertically stacked Empire State Buildings. Yet they fold away with ease. These seemingly contradictory attributes perplexed Kazuya Saito, an aerospace engineer at the University of Tokyo and the lead author of the study. Joanna Klein
NEARLY A DECADE NURSING? STUDY PIERCES ORANGUTANS’ MOTHER-CHILD BOND
Elizabeth Hunt Burrett, a mother from Australia, experienced a moment with an orangutan while breastfeeding her son at Meelbourne Zoo last year. As she tells it, the orangutan came over to watch, locked eyes with her and gave an affirming nod. “It was themost beautiful thing, ” she wrote in a widely circulated Facebook post. While it may be impossible to know exactly what this orangutan was thinking, it’s true that the critically endangered apes are exceptionally dedicated mothers. They give birth to one baby at a time, raising each for six to nine years, until it’s time to rear another. Mother and young sleep spend most of their time with only each other. And young orangutans nurse longer than any other mammal — sometimes into their ninth year of life, according to a study published in Science Advances on May 17.
Because observing wild orangutans can be difficult, the authors recreated the nursing history of four orangutans by analyzing barium, an element absorbed from maternal milk, in teeth taken from museum collections. In doing so, the scientists also discovered a possible clue why the apes nurse for so long: The teeth showed cycles in barium, which might correspond to environmental fluctuations in food.
The Southeast Asian rain forests orangutans call home are challenging environments, with unpredictable booms and busts in fruit, the animals’ most important food, said Tanya Smith, an associate professor in the Australian Research Center for Human Evolution at Griffith University and an author of the paper.
“When times are tough, adult orangutans will fall back on things like bark or hard seeds,” she said. “But offspring may not have the ability to eat some of these foods, or the knowledge to find them on their own, so they’re maybe falling back on mothers’ milk during periods of scarcity.” These are the first findings tying nursing to food scarcity in a primate, Smith added.
Previously, researchers estimated that orangutans wean off maternal milk between 6 to 8 years old, but they could never be sure because field surveys of the animals are tricky: Offspring often suckle inconspicuously, high up in trees or at night, and even when suckling is observed, it’s hard to know whether the animals are consuming milk or just comfort nursing, with no milk transfer.