Scientists have long thought humpbacks loners. New research shows this isn’t so: Researchers have observed some female whale form friendships that last for years. The behavior has only been observed in lady humpbacks of similar age, with the whales going their separate ways during the breeding season, but reuniting in the open ocean each summer. These bonds can be quite strong: the longest association endured for six years.
The study appears in the journal Behavioral Ecology and Sociobiology, and it also found that the whales with the longest-lasting associations gave birth to the most calves–another animal kingdom example that friendship is beneficial. The whales are probably improving their feeding efficiency, suggests lead author Christian Ramp.
“Staying together for a prolonged period of time requires a constant effort. That means that they feed together, but likely also rest together…. So an individual is adapting its behaviour to another one.” [BBC]
“There are lions and cheetahs and leopards out there, my dear. You’d be better off staying here with me.”
This is how male topi antelope lie for sex.
The area of Kenya where they live, Masai Mara National Reserve, is indeed filled with large predators that find antelopes to be just delicious, and so the topi have developed warning calls that they sound when it’s time to scurry away or else be eaten. But, according to an American Naturaliststudy, the devious topi males have figured out how to use their calls to fake the threat of immediate danger and keep females around, according to research leader Jakob Bro-Jørgensen.
From February to March, male topi hold small territories through which receptive females pass to assess each male’s mating potential. The authors noticed that, while a female in estrus was on a male’s territory, the male would sometimes emit alarm calls, even in the complete absence of a predator. These false alarms are acoustically indistinguishable from true alarm snorts [Ars Technica].
When it comes to the relationship between bees and African elephants, size does not matter. The massive pachyderms are terrified of bees, which can painfully sting elephants around their eyes and inside their trunks. Baby elephants are the most vulnerable to bee stings, as their skin isn’t thick enough to ward off the insects. And researchers have now found that the elephants have developed a special strategy to help them avoid these bees that scare the bejesus out of them.
When an elephant takes note of a swarm of bees, it emits a distinct rumbling call. This bee alarm, which the scientists termed a “bee rumble,” helps draw the herd’s attention to the bees and allows them to run off unharmed, the researchers write in the journal PloS ONE. What’s more, they respond to an audio recording of the bee rumble as if it were the real thing, giving farmers a tool they could potentially use to fend off unwanted elephants.
Do chimpanzees truly understand the concept of death–and do they grieve for their dead? Two separate studies due to be published in journal Current Biology suggest that chimps may have emotional responses to death that aren’t so different from humans’ reactions.
In the first study, researchers observed an ailing female chimp in a Scottish zoo. The elderly chimp, called Pansy, was believed to be more than 50 years old. As Pansy’s health began to falter, other chimps, including Pansy’s daughter, began to exhibit signs of concern that seemed remarkably human. They groomed Pansy more often than usual as she became lethargic, and after her death, her daughter stayed near the body for an entire night, even though she had never slept on that platform before. All of the group were subdued for several days afterwards, and avoided the place where she had died, spending long hours grooming each other [BBC].
In the second study, scientists working in the forests of Guinea observed two chimp mothers carrying around the bodies of their dead infants for weeks after their deaths. One chimp carried her dead baby around for more than 60 days, an unusually long period, according to the scientists. During the period, the babies’ bodies slowly mummified as they dried out. The bereaved mothers used tools to fend off flies [BBC].
For an in-depth examination of what these two studies reveal about our closest ancestor’s understanding of death and mortality, read Ed Yong’s post in the DISCOVER blog “Not Exactly Rocket Science.”
It’s not just that some birds can use tools, as primates can. Their smarts stretch even further: New research this week suggests that New Caledonian crows can solve a three-step problem, in which the three steps must be completed in succession to reach a tasty snack. Alex Taylor and colleagues document this discovery in the Proceedings of the Royal Society B.
Here’s the setup: There’s a short stick dangling from the bird’s perch on a string. That short stick isn’t long enough to grab the food that’s tucked inside a long and narrow box, but there’s a longer stick in a separate box. If the birds could figure out the first two steps—grabbing the short stick, and using it to get the longer stick—then voila, they could use the longer stick to reach the food.
Many children have a “bug period”–a time of life when bugs and creepy crawlies are a source of endless fascination and learning. Naturalist Edward O. Wilson jokes that unlike other kids, he never grew out of his bug period.
Luckily for this biologist, his lifelong passion for ants has yielded a career rich in accomplishment and accolades. He is not just the world’s preeminent expert on the social behavior of ants, but also the recipient of the National Medal of Science and two Pulitzer Prizes for nonfiction. Now, at the age of 80, Wilson has taken a stab at fiction. His first novel, Anthill, combines two of his greatest loves–his childhood home, Alabama, and the ants that have been his lifelong friends.
Described as an “six-legged Iliad,” Wilson’s Anthill draws parallels between human and ant societies. Though there are no ant symphony orchestras, secret police, or schools of philosophy, both ants and men conduct wars, divide into specialized castes of workers, build cities, maintain infant nurseries and cemeteries, take slaves, practice agriculture, and indulge in occasional cannibalism, though ant societies are more energetic, altruistic, and efficient than human ones [The New York Review of Books].
The book’s first and third sections deal with the adventures of an Alabama boy named Raphael Semmes Cody, called Raff. The boy grows up poking around the lush pine savanna of the Nokobee Tract; he’s drawn to its natural wonders, and uses the forest to escape from his parents’ toxic marriage. In this pristine woodland he literally leaves no stone unturned as he discovers the forest’s rich flora and fauna. Raff grows up and heads to Harvard to study law, returning later in life to protect the Nokobee from feckless developers. But fans of Wilson’s science will be most interested in the book’s middle section, where the author inserts a mini-novella describing the trials and tribulations of the ants living in the endangered forest.
When you see a flock of birds flying in formation, it might seem like their group dynamics are fairly simple: The one out front leads the way. But does the same birds always take the lead in a group? And do the birds in the back follow the overall leader, or rather the middle managers in front of them?
To find out, Tamás Vicsek and colleagues strapped backpacks equipped with GPS sensors to pigeons for a study out this week in Nature. The lightweight trackers recorded the birds on both solo flights and group flight and measured their positions five times per second. Indeed, Vicsek found, birds fly according to the group pecking order, with the leader out front. When it changed direction, its direct followers would do the same in less than a second, and then the more junior members of the group would respond to the direction of those middle managers.
But there were surprises, too. Sometimes the lead bird wouldn’t fly out front; it may have been tired from leading the pack and needed some time off. So perhaps birds are like cycling teams, occasionally trading off who carries the taxing burden of leading the group.
For more details about the study—including why it’s not as obvious as you might think that the leading bird flies in the front of the group, and why left and right matter so much to pigeons—check out DISCOVER blogger Ed Yong’s post at Not Exactly Rocket Science.
When it comes to picking up clever tricks and learning to do something the way everybody else does it, social animals like humans, birds, and monkeys excel. One individual looks at what others in the group are doing and quickly learns to follow suit—an invaluable skill that scientists previously thought evolved in step with communal living.
But what about an individual that doesn’t live in a group and spends most of its life in solitude–would it still have that ability to watch and learn? Cognitive biologist Anna Wilkinson set out to answer that question by studying the red-footed tortoise, one of the loneliest beasts on the planet. These South American tortoises grow up without parents or siblings, and adults rarely cross paths. If a head-bobbing display determines that a stranger is of the opposite sex, the two will mate perfunctorily–otherwise they just ignore each other [ScienceNOW]. Yet in a new study published in Biology Letters, Wilkinson showed that even these hermits possess the ability to learn by watching others.
Cleaner fish have a pretty good little business going. These select species of small underwater inhabitants set up “cleaning stations” where they eat parasites and dead tissue off larger fish. Sure, it might not be a gourmet meal, but in exchange for the service the large fish don’t eat the cleaners.
In some cases a pair of fish work in tandem, and a new study has found that males will punish their female partners if the females go overboard and eat more of the client than they should. While the research shows that fish, like people, can be aggrieved on behalf of a third party, don’t be too impressed with the males’ altruism—they get plenty out of the deal.
For a study in Science, researchers looked at the fishLabroides dimidiatus, whose females usually play by the rules of the cleaning business. But the females can sometimes be too greedy and “bite the flesh of the fish they are cleaning in a bid to get to the mucus, which is more tasty than the parasites on the surface,” researcher Redouan Bshary found. The male fishes, which are bigger in size, would then step in to chase the females away [AFP].
Like humans, sea stars enjoy lounging on the shore during the hot summer months. But when they get too hot, they can’t run for shade, so they have a back-up plan—fattening themselves with cold ocean water before the tide recedes, according to new research published in the journal The American Naturalist. This finding shows that sea stars, or ochre starfish, aren’t as helpless as previously thought. The sea stars are likely cued during low tide that it’s a hot day, the researchers say, and that signals them to soak up more water during the next high tide. “It would be as if humans were able to look at a weather forecast, decide it was going to be hot tomorrow, and then in preparation suck up 15 or more pounds of water into our bodies,” said study researcher Brian Helmuth [LiveScience]. Talk about staying hydrated.
The researchers first studied starfish in an aquarium using heat lamps to simulate a scorching summer day, an infrared camera to measure their internal temperatures, and a scale to weigh the sea stars and determine how much water they had absorbed. The researchers say the amount of water a starfish absorbs can decrease its body temperature by almost 4 degrees Celsius. But researcher Sylvain Pincebourde is concerned that this novel strategy may have limitations in a rapidly changing world…. As oceans warm together with air temperature the thermoregulatory mechanism used by the starfish will cease to work, he warns. “The colder the sea water, the more it is able to lower its body temperature. The efficiency of this thermoregulation strategy therefore might be annihilated by ocean warming” [BBC News]. Yet another reason to get a handle on global carbon emissions.
Great white sharks, much like humans, tend to stick to familiar turf, according to new research. Also like a lot of people, they like to hang out along the coastal waters of California. Sharks tagged with acoustic devices often spent up to 107 days at four key sites along the central and northern California coast where seals and sea lions are abundant: Southeast Farallon Island, Tomales Point, Año Nuevo Island and Point Reyes [LiveScience]. A few of the fearsome predators were tracked as far inland as the Golden Gate Bridge, apparently in search of snacks, say the researchers. The study, the largest and most detailed study of North American great white sharks, provides evidence contrary to the popular notion of great white sharks swimming aimlessly in the ocean.
The sharks under study divided most of their time between three locations: Northern California, Hawaii, and an area that the researchers called the white shark café, a spot in the open ocean about halfway between the Baja Peninsula and the Hawaiian Islands. Exactly what goes on at the café is still unknown–although researchers suspect it may be a hot spot for mating. Lead researcher Salvador Jorgensen explains that male white sharks “converge in a very specific area of the cafe,” Jorgensen said, while female sharks move in and out of the area. “It adds a little more evidence to the argument that this could be an important reproductive area” [Washington Post].
The scientists tracked the snaggly toothed predators between 2000 and 2008 from the Bay Area to San Diego, Hawaii and back as the sharks followed a route that was carried out with surprising precision and under a strict time frame [San Francisco Chronicle]. These great whites have been isolated from other great white sharks near Australia and South Africa for so long that they are now genetically distinct. The study was published in the journal Proceedings of the Royal Society B.
According to legend, the infamous Tsavo man-eating lions dined on 135 people near a Kenyan labor camp prior to their capture in 1898. The two maneless lions have been a crowd favorite at Chicago’s Field Museum, where the stuffed beasts have been on display for over 80 years. But after analyzing fragments of the lions’ bones and fur, scientists at the University of California in Santa Cruz have determined that the true number of humans eaten by the lions was likely closer to 35.By comparing isotopes in the lions’ samples with their normal prey of zebra, wildebeest and buffalo, with other lions, and with the remains of 19th century Kenyans, the scientists estimated that one of the lions ate 24 humans, while the other ate 11[Chicago Tribune].The results suggest that the lions hunted together but didn’t always share food, which makes the pair the first example of a cooperative hunting group that ate different prey.
The two lions developed a taste for man after drought, pestilence, and hunting killed of most of their usual prey, according to previous research. Also, the Tsavo lions lived near a slave trading route, which offered easy access to sick, injured, or dead slaves. The lions dragged people from tents at night…. After nine months of this, the beasts were finally killed in December [Nature News]. The recent analysis suggests one of the lions had developed a toothache, which made eating humans easier than devouring its normal prey. The study attributes 24 deaths to one cat, or 30 per cent of its diet, and 11 deaths to the other, just 13 per cent of its food[New Scientist].
Colonel John H. Patterson, a British engineer, shot the lions and then wrote a book about their killing spree, claiming that “28 railroad workers and scores of unfortunate Africans” had been killed [Chicago Tribune]. Some believe that in order to boost the selling price of the lions, he exaggerated the lions’ man-killing ways and inflated the death count to 135. Patterson sold the lion skins for $5,000 to the Field Museum in 1924.
The current study appears in the journal Proceedings of the National Academy of Sciences.
Before one species of jumping spider, known as Evarcha culicivora, goes trolling for a mate, it firsts look to feast on blood-fattened mosquitoes. What happens next seems like something out of a bad video game: The delicacy gives the spider a special power–a sweet smell that the opposite sex finds irresistible.
In a new study, which will be published in the Proceedings of the National Academy of Sciences, researchers exposed E. culicivora specimens to the odors of others raised on blood-fed female mosquitoes and on three other diets: sugar-fed females, males and lake flies…. [The] tested spiders of both sexes were most strongly attracted to the odor of spiders reared on blood-fed female mosquitoes. But the attraction was only for spiders of the opposite sex [The New York Times]. Spiders would hang around blood-fattened spiders of the opposite sex four times longer than they would linger around those fed on another diet. The blood perfume effect might only be triggered by a gender specific hormone, the researchers suggest.
A jumping spider that passes on eating ants in favor of leafy greens has just been described by scientists. The novel arachnid, named Bagheera kiplingi, is exciting because it is the first-known predominantly vegetarian spider; all of the other known 40,000 spider species are thought to be mainly carnivorous [BBC News]. The study was published in the journal Current Biology.
Found in Central America and Mexico, the order-defying jumping spider eats nutrient-rich structures called Beltian bodies, which are found on the tips of Acacia trees. Trees produce the bodies to feed ants that defend them, which is a textbook example of what’s called co-evolutionary mutalism, and one that B. kiplingi has evolved to exploit [Wired.com].Despite a primarily veggie diet, B. kiplingi actively hunts its green prey, which sounds bizarre, since the leaves can’t run away.The spiderfirst sits and stalks its target before it dodges through the ant defenses, snatches a Beltian body, and flees to safety.
Following up on today’s earlier post about alcohol and brain injuries, we bring you a study on alcohol and risk taking behavior. It seems obvious that drinking alcohol would lead to immediate risk taking, but does drinking as a teenager lead to risk taking behavior as an adult? Some researchers have suspected as much, but they haven’t been able to rule out the possibility that risk-prone people simply start drinking at an earlier age. So a research group chose an obvious course of action to test the idea—they got a bunch of rats drunk and let them gamble.
The researchers tested two groups of genetically identical rats, one group that was fed a normal diet and another that boozed it up. To get the rats drunk, the researchers borrowed the tried-and-true approach of frat boys everywhere—they fed them Jell-O shots. The rats went on a 20 day bender and were tested for risky behavior 3 weeks later, when they were adults, using a gambling task. The animals learned that pressing one lever produced small but certain rewards in the form of small sugar pellets and an adjacent lever yielded bigger rewards—more pellets—but paid off less frequently. The researchers rigged the game so that in some testing sessions choosing the certain reward was the best overall strategy, while in other sessions the “risky” lever yielded the greatest overall payoff [ScienceNOW Daily News].
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].
Scientists have long thought humpbacks loners. New research shows this isn’t so: Researchers have observed some female whale form friendships that last for years. The behavior has only been observed in lady humpbacks of similar age, with the whales going their separate ways during the breeding season, but reuniting in the open ocean each summer. These bonds can be quite strong: the longest association endured for six years.
“There are lions and cheetahs and leopards out there, my dear. You’d be better off staying here with me.”
Many children have a “bug period”–a time of life when bugs and creepy crawlies are a source of endless fascination and learning. Naturalist 
When you see a flock of birds flying in formation, it might seem like their group dynamics are fairly simple: The one out front leads the way. But does the same birds always take the lead in a group? And do the birds in the back follow the overall leader, or rather the middle managers in front of them?
When it comes to picking up clever tricks and learning to do something the way everybody else does it, social animals like humans, birds, and monkeys excel. One individual looks at what others in the group are doing and quickly learns to follow suit—an invaluable skill that scientists previously thought evolved in step with communal living.
Cleaner fish have a pretty good little business going. These select species of small underwater inhabitants set up “cleaning stations” where they eat parasites and dead tissue off larger fish. Sure, it might not be a gourmet meal, but in exchange for the service the large fish don’t eat the cleaners.
Like humans, sea stars enjoy lounging on the shore during the hot summer months. But when they get too hot, they can’t run for shade, so they have a back-up plan—fattening themselves with cold 
Great white sharks, much like humans, tend to stick to familiar turf, according to new research. Also like a lot of people, they like to hang out along the coastal waters of California. 
According to legend, the infamous 
Before one species of jumping 
Following up on today’s earlier post about 
