11 Buoyant Facts About Humpback Whales

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Humpback whales are some of the most intelligent animals on the planet. Hunted almost to extinction during the 19th and early 20th centuries, their populations are slowly recovering, and now they’re a favorite sight for whale-watchers. Here are 11 facts you might not have known about the mysterious marine giants, who are known for their acrobatics and for sidling right up alongside boats to get a good look at their human observers.

1. THEY’RE LONGER THAN A SCHOOL BUS.

North American school buses max out at about 45 feet long. Female humpback whales—which are larger than males—can be up to 60 feet long, and their pectoral fins alone can be 15 feet long. At birth, humpbacks weigh around 1 ton, doubling in size during their first year of life and eventually reaching up to 40 tons.

2. THEY HAVE HUGE MOUTHS.

In keeping with the rest of their bodies, their mouths are huge—their tongue alone is the size of a small car. But the opening to their throat is only about the size of a grapefruit, according to the Hawaiian Islands Humpback Whale National Marine Sanctuary, so they can’t swallow large prey. Instead, they eat krill, small fish, and plankton. They can eat up to a ton of food per day, according to the 2015 documentary Humpback Whales.

3. THOSE BUMPS ARE HAIR FOLLICLES.

Each of the distinctive bumps along a humpback’s head holds a single hair that the whale uses to sense the environment around it. These hairs help the whale glean information about water temperature and quality.

4. THEIR FLUKES ARE LIKE FINGERPRINTS.

Like human fingerprints, humpback tails can be used to identify individuals. The pigmentation and scarring on their flukes is unique, and scientists document these markings to keep track of certain whales that they see repeatedly during their research trips.

5. THEY LIVE A LONG TIME, BUT NOT AS LONG AS MANY OTHER WHALES.

Most humpback whales make it into their 60s, but scientists estimate that they may live up to 80 years. Still, that’s nothing compared to bowhead whales, a species whose oldest known individuals have lived to be 200 years old.

6. THEY HAVE THE LONGEST MIGRATIONS OF ANY MAMMAL.

Each year, humpbacks migrate from their feeding grounds in cold waters toward warm breeding areas—Alaskan whales head to Hawaii, while Californian whales head to Mexico and Costa Rica, and Australian whales migrate to the Southern Ocean. These biannual journeys can involve distances of up to 5000 miles, which is officially the longest known migration of any mammal on earth.

The fastest documented migration of a humpback whale was observed in 1988, when a humpback traveled from Sitka, Alaska to to Hawaii in just 39 days—or possibly less, depending on how soon it left Alaskan waters after the researchers sighted it the first time [PDF]. That’s a journey of about 2750 miles point to point.

7. THEY HAVE BEEN KNOWN TO DEFEND OTHER SPECIES FROM ORCAS.

In 2009, marine ecologist Robert Pitman watched two humpback whales rescue a seal from a group of orcas that were pursuing it. The seal ended up on one of the humpbacks’ chests, and when it began to fall off, the whale even nudged it back on with a flipper, indicating that it was an intentional act of altruism. Though it’s not entirely clear why they would do so, it appears to be an offensive response on the part of the humpbacks, who may intervene whenever they hear killer whales fighting, whether one of their own is involved or not.

8. ONLY THE MALES SING.

Their songs may have made the species famous, but not every humpback sings. It’s strictly a male behavior, and plays an important part in courtship displays. There’s plenty of mystery that still surrounds the science of whale songs, but in 2013, researchers discovered that it’s a group activity that involves even sexually immature males. Both young and mature whales sing in chorus, giving the immature whales a lesson in singing and courtship behavior, and helping older whales amplify their songs to draw females to the area from afar. Other research has found that these songs change over times, and whales learn them much like a human learns a new song, bit by bit.

9. BREACHING IS LIKE YELLING

Though humpbacks are famous for their songs, that’s not the only way they communicate. Scientists only recently discovered that breaching—when whales jump up into the air, crashing back down into the water—is a way to keep in touch with far-away friends. Humpbacks leap higher and more often than other whales, and while spectacular to witness, the moves come at a cost: It takes a lot of energy, especially when the whales are fasting. But after 200 hours observing humpbacks migrating past the Australian coast, a team from the University of Queensland found that the whales were more likely to breach when the nearest group of other humpbacks was more than two and a half miles away, and that they were more likely to do so when it was windy out. It appears that breaching is a way to communicate over long distances when there is a lot of competing noise.

10. THEIR SONGS ARE INCREDIBLY COMPLEX …

Humpback songs aren’t just showy. They have their own grammar, and their songs are hierarchical, like sentences. In human language, this means that the meaning of sentences depends on the clauses within them and the words within them. In 2006, mathematical analysis found that humpbacks use phrases, too. And they remix their tunes, too, tweaking them and changing them over time, often combining new and old melodies. Humpback songs have even been visualized as sheet music.

11. … AND HELPED END WHALING.

Researchers estimate [PDF] that prior to the whaling boom of the 19th and 20th centuries, there were around 112,000 humpbacks in the North Atlantic alone, but that by the time commercial whaling was banned in the region in 1955, there were less than 1000 individuals left. Between 1947 and the 1970s, the USSR alone killed an estimated 338,000 humpbacks, falsifying data it was required to submit to the International Convention for the Regulation of Whaling to disguise the illegal magnitude of its hunting operation. It has been called “one of the greatest environmental crimes of the 20th century.”

While the populations have grown and humpbacks have been taken off the endangered species list, some estimates put the worldwide humpback population at only 40 percent of what it was before the whaling era. Whaling was banned throughout the rest of the world in 1966, though Norway, Iceland, and Japan still practice it.

Roger Payne, one of the scientists who first discovered that humpbacks sing songs, later became instrumental in pushing to protect the species in the 1960s. In 1970, he released his recording of humpback songs as a record, which remains the best-selling nature recording in history. In 1972, the songs were played at a Greenpeace meeting, and ended up galvanizing a new movement: Save the Whales. “It certainly was a huge factor in convincing us that the whales were an intelligent species here on planet Earth and actually made music, made art, created an aesthetic,” as former Greenpeace director Rex Weyler told NPR in 2014. The campaign gained traction with other organizations, too, and helped lead to the International Whaling Commission’s 1982 whaling ban.

Chimpanzees Bond by Watching Movies Together, Too

Windzepher/iStock via Getty Images
Windzepher/iStock via Getty Images

Scientists at the Wolfgang Kohler Primate Research Center in Germany recently discovered that, like humans, chimpanzees bond when they watch movies together, the BBC reports.

In the study, published in Proceedings of the Royal Society B, researchers stationed pairs of chimpanzees in front of screens that showed a video of a family of chimps playing with a young chimp. They found that afterward, the chimps would spend more time grooming and interacting with each other—or simply being in the same part of the room—than they would without having watched the video.

They gave the chimps fruit juice to keep them calm and occupied while they viewed the video, and they chose a subject that chimps have previously proven to be most interested in: other chimps. They also used eye trackers to ensure the chimps were actually watching the video. If you’ve ever watched a movie with friends, you might notice similarities between the chimps’ experience and your own. Drinks (and snacks) also keep us calm and occupied while we watch, and we like to watch movies about other humans. Since this study only showed that chimps bond over programs about their own species, we don’t know if it would work the same way if they watched something completely unrelated to them, like humans do—say, The Lion King.

Bonding through shared experiences was thought to be one of the traits that make us uniquely human, and some researchers have argued that other species don’t have the psychological mechanisms to realize that they’re even sharing an experience with another. This study suggests that social activities for apes don’t just serve utilitarian purposes like traveling together for safety, and that they’re capable of a more human-like social closeness.

The part that is uniquely human about this study is the fact that they were studying the effect of a screen, as opposed to something less man-made. The chimps in question have participated in other studies, so they may be more accustomed to that technology than wild apes. But the study demonstrates that we’re not the only species capable of social interaction for the sake of social interaction.

[h/t BBC]

10 Facts You Should Know About Mosquitoes

tskstock/iStock via Getty Images
tskstock/iStock via Getty Images

Between the itching and the welts and the fears of mosquito-borne viruses, it's easy to forget that mosquitoes are a wonder of evolution, and that maybe they don't get a fair shake from us. Of more than 3000 known species, only 80 actually bite people, and at least one eats other mosquitoes for us. They grow from egg to adult in just five days, begin mating within minutes of hatching, and possess, by way of their stinging mouthparts, some of the coolest appendages in the animal kingdom.

1. Mosquitoes are excellent flyers in bad weather.

The average raindrop is 50 times heavier than the average mosquito, yet they buzz around in the rain with no problems. If a Boeing 747 got whacked with a similarly scaled-up raindrop, there would be 2375 tons of water coming down on it, and things probably wouldn’t turn out as well as they do for the mosquito. How do the insects do it?

A common urban legend said that the bugs were nimble enough to dodge the drops. A few years ago, a team of engineers from the Georgia Institute of Technology watched real mosquitoes and Styrofoam dummy mosquitoes with a high-speed camera during a rainy flight to see if that’s what was really happening. They found that the bugs don’t fly fast enough to dodge the drops, but their slowness is what keeps them from getting knocked out of the sky. A mosquito’s low mass even at slow speed doesn’t provide enough of a target for a raindrop to splash on collision. Instead, the drop just deforms, and doesn’t transfer enough momentum to the mosquito to disrupt its flight.

2. Texas is the mosquito capital of America.

Of the 3000 species of mosquitoes around the world, at least 150 are found in the United States, and 85 of those call Texas home. When people say everything's bigger in Texas, you can also include the biodiversity of the state's biting, disease-carrying insects.

3. Some mosquitoes are truly dangerous to humans ...

The female mosquito, which is the one that stings and sucks blood, is an incredible transmitter of disease and, because of that, the deadliest animal in the world. Each year, the malaria parasites they transmit kill 2 million to 3 million people and infect another 200 million or more. They also spread pathogens that cause yellow fever, dengue fever, Rift Valley fever, Chikungunya and West Nile disease.

4. ... and some mosquitoes are harmless.

Not every species of mosquito sucks blood from people, and among those that do, not every one transmits disease. The blood suckers don’t even need to bite you for every meal. Males live entirely on nectar and other plant fluids, and the females’ diet is primarily plant-based, too. Most of the time, they only go after people when they’re ready to reproduce, because blood contains lipids, proteins, and other nutrients needed for the production of eggs.

5. MosquitoEs actually help the environment.

When you’re rubbing calamine lotion all over yourself, mosquitoes might not seem to serve any purpose but to annoy you, but many species play important ecological roles. The mosquitoes Aedes impiger and Aedes nigripes, which gather in thick clouds in Arctic Russia and Canada, are an important food source for migrating birds. Farther south, birds, insects, spiders, salamanders, lizards, frogs, and fish also eat different mosquito species regularly. Plants need them, too, and some, like the blunt-leaved orchid and endangered monkeyface orchid, rely on mosquitoes as their primary pollinator.

Some mosquito species are also excellent at mosquito control. Species of the genus Toxorhynchites feed on the larvae and immature stages of other mosquitoes and will sometimes even cannibalize members of their own species.

6. Mosquitoes are amazing hunters (as if we needed to tell you that).

Mosquitoes are adept at picking up on the chemicals given off by their human hosts. They can detect the carbon dioxide in our breath, the 1-octen-3-ol in our breath and sweat, and other organic substances we produce with the 70-plus types of odor and chemical receptors in their antennae. These receptors can pick up traces of chemicals from hundreds of feet away, and once the mosquito closes in, it tracks its meal chemically and also visually—and they’re fond of people wearing dark colors.

7. Mosquitoes can be picky.

If it seems like you’re always covered head to toe by bites while people who were sitting right next to you only have one or two, it’s not just paranoia; the skeeters actually are out to get you. Some people happen to give off more of the odors and compounds that mosquitoes find simply irresistible, while others emit less of those and more of the compounds that make them unattractive to mosquitoes—either by acting as repellents or by masking the compounds that mosquitoes would find attractive.

8. A female mosquito's mouth is primed for sucking blood.

A mosquito doesn’t simply sink its proboscis into your skin and start sucking. What you see sticking out of a mosquito’s face is the labium, which sheaths the mouthparts that really do all the work. The labium bends back when a mosquito bites, allowing these other parts to pass through its tip and do their thing. The sharp, pointed mandibles and maxillae, which both come in pairs, are used to pierce the skin, and the hollow hypopharynx and the labrum are used to deliver saliva and draw blood, respectively.

9. Mosquito saliva prevents blood clotting.

The saliva that gets pumped out from the hypopharynx during a bite is necessary to get around our blood’s tendency to clot. It contains a grab bag of chemicals that suppress vascular constriction, blood clotting and platelet aggregation, keeping our blood from clogging up the mosquitoes' labrum and ruining their meal.

10. Mosquitoes can explode.

Blood pressure makes a mosquito's meal easier by helping to fill its stomach faster, but urban legend says it can also lead to their doom. Story goes, you can flex a muscle close to the bite site or stretch your skin taut so the mosquito can’t pull out its proboscis and your blood pressure will fill the bug until it bursts. The consensus among entomologists seems to be that this is bunk, but there is a more complicated way of blowing the bugs up. To make a blood bomb, you’ve got to sever the mosquito’s ventral nerve cord, which transmits information about satiety. When it's cut, the cord can’t tell the mosquito’s brain that its stomach is full, so it’ll keep feeding until it reaches critical mass. At least one researcher found that mosquitoes clueless about how full they were would keep sucking even after their guts had exploded, sending showers of blood spilling out of their blown-out back end.

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