animal behavior Archives - Page 6 of 7

The FWP weekly digest of wondrous wildlife happenings
and other interesting items from the natural world

Creatures to meet | Things to learn
Things to do

Lisa S. French

2-minute read

If one of your New Year’s resolutions is to polish your signature dance move (and we know you have one), researchers in Japan and Sweden offer some thought-provoking new insights into the ancient origins of your distinctive locomotive stylings. The integration of movement and sound, resulting in that splendid thing we do, known as dancing, is widespread across human cultures, dating back as far as 1.8 million years. While animals in the wild, including elephants, kangaroos, and rabbits produce drumming and stomping sounds to communicate, and some species of animals in captivity such as sea lions and parrots have been trained to move to a beat, it was believed that homo sapiens were unique in our ability to spontaneously produce rhythmic movements in response to musical sounds.

A recent analysis from Kyoto University exploring the biological foundation of music-induced movement in non-human primates points to a gradually developing connection between motor and auditory areas of the brain over millennia. In a controlled study, chimpanzees voluntarily responded to both random and regular beats with rhythmic swaying, implying a possible evolutionary link to musicality that may have developed from a common ancestor around 6 million years ago. Although male chimpanzees in the wild drum, make sounds with objects, chorus in groups, and display rhythmic movement in response to heavy rainfall, they have not been observed to interact in a synchronous manner with musical sounds. However, the chimpanzees in the Kyoto study did move toward the sound of the beat and engage by swaying, hand-clapping, foot-tapping, and vocalization. Unlike humans who show no gender-related differences in musical ability, consistent with communication hierarchies within their patriarchal societies, male chimpanzees were more likely to get into the swing of things than females.

Researchers at Lund University have come up with an alternative theory, that the roots of our rhythmic behavior, while still evolutionary, may lie closer to home—in our mother’s ability to walk the upright walk. Compared to the irregular gait of non-human primate quadrupeds like the chimpanzee, the footfall of human bipeds is evenly paced at around 120 beats per minute, mimicking universally recognized tempos. Because the consistent sound and vibration of the mother’s footfall is heard and felt by a developing human fetus beginning at about 24 weeks, this is thought to have a strong influence on the formation of musical abilities, more so than the sound of the maternal heartbeat which is similar across primates. The researchers have theorized that the cadence of footfall is encoded into the limbic system of the human fetal brain. This bit of grey matter is primarily responsible for emotion and memory, which is why it is believed we respond positively as newborns and in later life to musical rhythms because they closely resemble the sounds we perceived in the environment of the womb. If you get that “I know this one” feeling when you hear a regularly timed beat, you may have picked it up in the interior maternal soundscape before you were born courtesy of your mother who walked an average of 10,000 equally spaced steps in a typical day of roaming. And if you often feel compelled to get up to get down, you might have mom to thank for that as well.

While chimps appear to have some limited ability to move rhythmically, both studies indicate that humans are still top banana when it comes to synchronizing to a beat; however, further investigation may eventually reveal that we’ll have to make room on the dance floor for our swinging friends.

As a lucky member of the community of living beings who can dance if they want to, here’s hoping you find your idiosyncratic joy-inducing groove in 2020. Beaming out positive vibes of transformative change from Weekly Wondrous for a shiny New Year ahead. Would that not be nice!

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Lisa S. French January 6, 2020

Exceptionally Eel-ectric

Compared to many of the creatures featured on Weekly Wondrous, the electric eel (Electrophorus electricus) scores relatively low on the cuddlesome quotient, however, what the high-voltage South American river dweller lacks in animal magnetism, it makes up for in shock value. And the most shocking eel of them all, the new species Electrophorus voltai, was discovered this fall by scientists at Smithsonian’s National Museum of Natural History.

But before we get to that electrifying story, perhaps you are wondering, “What are eels, anyway? Reptiles? Amphibians? Fish? Amphishians?” Strictly speaking, electric eels are not true eels but a species of electric fish—long, blade-shaped knifefish to be exact, and more closely related to carp and catfish than eels. The 800-plus species of true eels primarily live in saltwater, while electric eels can only be found in the murky freshwater habitats of the Amazon and Orinoco Rivers. It was there, in the highland waters of the Brazilian Shield, that the approximately 8-foot long, 860-volt-producing Electrophorus voltai was identified—the strongest living bioelectricity generator known to date. To put that impressive eel power into perspective, the human body is only capable of producing and transmitting between 10 and 100 millionths of one volt over a distance of approximately one-millionth of a meter, a fact for which those of us who travel by crowded subway are quite grateful.

Like all species of electric eels, the E. voltai produces its record-breaking current through the stimulation of thousands of synchronized stacked cells called electrocytes in three pairs of electric organs that take up 80% of the length of its body. The Smithsonian researchers theorize that the 30% increase in electricity-generating potential from the highest previously recorded E. electricus measurement of 650 volts may be an adaptation to the reduced conductivity of the waters where the E. voltai species began its evolution about 7.1 million years ago.

Electric eels make full use of their innate ability to self-generate jolts, utilizing their piscine electro-pulses for eel-to-eel communication, navigation, self-defense, and to locate and stun small fish and invertebrate prey. The objects of the carnivorous fish’s shocking attentions are captured through a highly effective two-step strategy, which researchers at Vanderbilt University have compared to a type of remote control. First, the eel transmits an electric pulse, which causes whole-body contractions in its prey, revealing its location, then a second shock is administered to immobilize the target for ease of swallowing.

In case you are curious as to how eels manage to avoid electrocuting themselves when they get down to their meal-zapping business, one hypothesis is that the amount of the electricity flow is small in proportion to the eel’s body but significant to the size of its prey, and of very short duration (about two milliseconds). In addition, a large percentage of the current dissipates into the water, further reducing its impact on the eel’s critical organs.

Studying and understanding how eels generate and transmit electricity has inspired all manner of technological and medical innovations that benefit humankind, ranging from the first electric battery in 1799 to the ongoing development of soft robots, cardiac pacemakers, and artificial organs. While an effort has been made to determine what it would take to run a Tesla Model 3 on eel power for one hour, the estimated requirement of 7,200 eels in 144,000 gallons of water indicates that particular research endeavor to be a non-starter for both the Tesla and the eels.

Two hundred and fifty years after the discovery of the first electric eel species in South America, the recent identification of the E. voltai in the same region is yet another compelling testament to the extreme importance of protecting and maintaining biodiversity hotspots like the Amazon. Given that approximately 85% of our planet’s flora and fauna remain to be discovered, it’s clear that preserving wild spaces is critical to the continued study of the living world. As biologist and naturalist E.O. Wilson writes in The Diversity of Species, “We should preserve every scrap of biodiversity as priceless while we learn to use it and come to understand what it means to humanity.”

Full disclosure: While eels are clearly some of the most remarkable creatures on Earth and can be strikingly beautiful, we empathize if you are somewhat eel-averse as we confess to hyperventilating a bit while researching this one. However, since getting fish-zapped outside of the Amazon is a low probability event, we can rest easy and simply file these slippery fellows under “admire from afar.”

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Lisa S. French October 31, 2019

Tree-Planting Tapirs

If the Brazilian tapir’s eye-catching ensemble of creature features brings to mind ancient beasts, that’s because the shy, primarily nocturnal South American megafauna is one of the oldest species of large mammal remaining on Earth. The origins of this floppy-nosed, bristly-maned, odd-toed ungulate date back approximately 35 million years. For the ungulate-uninitiated, tapirs are Perissodactyls, hooved herbivores who like their closest relatives horses and rhinoceros, possess an odd number of toes. The Brazilian, or lowland, tapir is one of four widely recognized species of tapir native to the forests, grasslands, and mountains of Central and South America and Southeast Asia.

Measuring five to eight feet long and weighing between 300 and 700 pounds, the Brazilian tapir maintains its impressive bulk by consuming up to an equally impressive 85 pounds worth of shoots, leaves, branches, and fruit a day. As it turns out, the tapir’s hearty appetite for seed-bearing plants plays an important role in restoring degraded rainforests. According to researchers at Ohio State University, 80 percent of trees in the Amazon are dependent upon animals for seed dispersal. One of the primary “gardeners of the rainforest” tapirs ingest and expel a large variety of seeds that have future tree potential. Results of a recent study carried out by scientists at the Amazon Environmental Research Institute in Mato Grosso, Brazil, found that 99 percent of 130,000 seeds passed through a tapir’s digestive systems intact. Seeds that survive the digestive process are more likely to germinate. And here’s where it gets more ‘oh, wow’ interesting: the Mato Grosso study suggests that tapirs may prefer to browse and graze in degraded plots of land rather than in unspoiled forest. When sunlight hits the earth as a result of tree canopy loss in burnt or degraded areas, it forces up and reveals tender green shoots from the forest floor that are attractive to tapirs. The tapirs observed in the study spent about twice as much time feeding in degraded plots resulting in more seed “deposits” in areas in need of reforestation.

In the Amazon, wildlife depend upon healthy forest systems, and as the Ohio State and Mato Grosso research indicates, healthy forest systems depend upon wildlife. The Brazilian tapir’s natural capacity to contribute to tree planting can be an important factor in helping to regenerate carbon-storing, rainforest habitat. That is why protecting an umbrella species like the tapir also serves to protect other animals in its ecosystem.

Despite their aptitude for seed dispersal, Brazilian tapirs alone can’t compensate for elevated rates of Amazon deforestation. In addition, as a result of rapid habitat loss due to wildfires and ongoing land-use change, as well as illegal hunting, populations of Brazilian tapirs are decreasing and currently listed as vulnerable by the IUCN. The good news is you can help keep the hooved horticulturalists of Central and South America in their gardening groove by supporting the tapir research of Nai Conservation and the conservation action plans of the Tapir Specialist Group.

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Lisa S. French October 2, 2019

Wondrous Whales

In honor of World Oceans Day, here’s a status update on one of the most precious inhabitants of the deep, blue Atlantic: Eubalaena glacialis, the good or true whale of the ice—population currently teetering at 411. Otherwise known as the eastern North Atlantic right whale, weighing up to 70 tons and measuring up to 55 feet long, this toothless, baleen cetacean, native to the Eastern Coast of the United States, is one of the largest mammals on earth. Dubbed the “right whale to hunt,” for centuries the docile, slow-moving North Atlantic right whale was prized for its blubber, oil, and baleen, resulting in over-exploitation and decimation of populations. Although the hunting of right whales was outlawed in 1935, this critically endangered species continues to face a number of extreme challenges to its survival including ship strikes, fishing gear entanglement, degraded habitat, underwater noise pollution, and more recently, declining prey.

As Atlantic waters warm due to climate heating, scientists believe that the enormous quantities of small crustaceans (Calanus finmarchicus) the right whales depend on for food are moving further north into shipping lanes and fishing areas that make strikes and entanglement more likely. Between 2010 and 2016, 85% of right whale deaths were caused by entanglement. In 2017 and 2018 there was an extremely high mortality rate of 20 right whales, and for the first time in 38 years in 2018, there were no calves born.

A normal life span for a North Atlantic right whale is 70 years. By age ten females are capable of reproduction and have a gestation period of one year. While right whales typically give birth to a single calf every three to five years, due to a host of environmental stressors, as of 2017 the interval between births had increased to ten years. Even though seven new calves have been spotted off the coast of Florida as of March 2019, at the current rate of loss and reproduction, without support and intervention, scientists predict the North Atlantic right whale could disappear from the planet in the next 20 years. You can learn more about the North Atlantic right whale and the network of scientific organizations working together to monitor populations, protect critical habitat, and reduce injury and mortality from vessel disturbance and fishing gear from the National Oceanic and Atmospheric Administration and the North Atlantic Right Whale Consortium.

And in other recent whale watching news, New York City and British Columbia are celebrating sightings of big humpbacks and baby orcas. Mind how you go, befinned friends, mind how you go…

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Lisa S. French June 8, 2019

Brainy Bees

As the days grow longer and buds burst into blooms, we’re on the lookout for the return of everybody’s favorite essential pollinator, the honeybee! If you have ever wondered why honeybees are so skilled at helping to transform flowers into fruit and veg like apples, avocados, blueberries, and broccoli, it’s because they’re wicked smart. How smart, you ask? Well, even though a honeybee’s brain is about 20,000 times smaller than a human brain, that seed-sized morsel of gray matter packs a lot of computing power. A honeybee brain is capable of managing 10 trillion computations a second—that’s 625 times the speed of most advanced supercomputers. Research conducted by scientists at the University of Melbourne indicates that honeybees can do basic arithmetic, understand the concept of zero, and learn and teach other bees how to gain rewards. All of that buzz-worthy brilliance is put to good use efficiently managing a complex series of tasks that contribute to the cross-pollination of 30 percent of human food crops and 90 percent of wild plants. Honeybees also use their smarts to locate prime floral real estate by color and smell and share the inside scoop on best bets for plentiful pollen and nectar with their hive mates through a complicated “waggle” dance language.

What’s more, these winged brainiacs are the ultimate team players, efficiently performing well-defined hierarchical functions within their colonies. The apis mellifera monarch’s, or queen honeybee’s, one and only job is to create more bees. The queen bee can lay up to 2,000 eggs a day which develop into queens, drones, or worker bees. The bees that you see buzzing about outside the hive collecting pollen and nectar from flowers are sterile female worker bees. Worker bees are also responsible for keeping the inside of the hive tidy as well as feeding the queen, drones, and bee larvae. Male bees or drones have only two functions in the hive, eating and mating with the queen. While that may sound like the good life, once a drone mates with the queen, it falls to the ground and dies. Drones that don’t make the cut with the queen are ejected from the hive by worker bees come winter.

Queen bees are not born to the throne. They are created through a process where larvae designated for insect royalty by their placement in special queen cells in the hive are fed exclusively the aptly named royal jelly. A milky substance that is secreted from glands in the heads of worker bees, royal jelly is composed of proteins, sugars, fatty acids, and trace minerals which help queens develop their reproductive capacity. Tasked with the very important job of keeping the colony humming with new offspring, a queen honeybee can live anywhere from one to six years, significantly longer than the seasonal life span of female worker bees and male drones.

Despite having an amazing capacity to problem solve and work collaboratively, one thing that honeybees have not been able to figure out on their own is how to protect themselves from the multiple factors including global heating, pesticide use, habitat loss, and parasites which have led to an estimated annual loss of over 30% of the honeybee colonies that are critical to pollinating one out of every three bites of the food we eat. According to the 2018-19 survey results from the Bee Informed Partnership, over the past winter, U.S. beekeepers lost 40% of their hives, which is the worst recorded loss since 2006.

It’s clear that when it comes to keeping global populations well-fed and environmental systems healthy and functioning, these tiny, brainy insects are the bee all end all. Whether you live in a big city, a small town, or somewhere in between, check out the Xerces Society’s tips on what to plant to create a safe haven for honeybees on your patch. You can also sponsor a hive through The Honeybee Conservancy and find Favorite World Press recommendations for pollinator-friendly seed bombs and supplies here.

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Lisa S. French May 27, 2019

Evolving Elephants

Unlike their Asian elephant cousins, both male and female African elephants grow tusks over the course of their lifetimes which they use for defense, debarking and moving trees, and digging for roots, salt, and water. These long incisors used as tools for daily living have made elephants targets of ivory poachers across the continent of Africa for centuries and to devastating effect. While it is extremely rare for male African elephants to be born without tusks, the 3 to 4 percent of wild female African elephants that never grow tusks have a distinct evolutionary advantage as they are more likely to survive periods of intense poaching. Scientists believe that through the process of natural selection, tuskless female elephants are passing this trait on to their daughters. As intensely hunted big tusked male elephants, known as tuskers, are eliminated from the population through poaching, the offspring of smaller tusked males and tuskless females spread the tuskless trait.

Researchers are now studying tuskless populations in heavily poached areas across Africa to determine what this growing phenomenon means for the future of the species. According to Dr. Joyce Poole of Elephant Voices, 51 percent of 200 adult females 25 years or older in Gorongosa National Park in Mozambique that survived the rampant poaching that took place during the 15-year civil war are tuskless. Since the civil war ended in 1997, 32 percent of female elephants born in Gorongosa are tuskless. In the early 2000s in Addo Elephant National Park in South Africa, 98% of 174 females were also observed to be tuskless. While current populations of tuskless elephants appear to be healthy and thriving, scientists are continuing to study the impact of tusklessness on both individual and group behaviors as well as on other plant and animal species in their native ecosystems. Through critical ongoing research, we’ll learn more about how these iconic, highly intelligent, and empathic animals are continuing to evolve and adapt to the growing human-induced pressures that impact their survival.

For breathtaking photos of some of Africa’s last great tuskers, check out Land of Giants by Will Burrard-Lucas.

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Lisa S. French March 19, 2019

Swinging Sifakas

You’d have to travel all the way to the island of Madagascar off of the eastern coast of Africa to find the wooly, wide-eyed, white-helmeted Coquerel’s sifaka in its native habitat. One of nine species of lemurs, these diurnal (active in day and night) highly intelligent primates, known as prosimians, evolved millions of years before monkeys and apes, their simian relatives. Primarily treetop dwelling herbivores, the long-legged sifaka is impressively agile, propelling itself distances of over 30 feet as it leaps and swings through the canopy of its dry forest home. For graceful ground travel, sifakas employ a two-legged sideways hopping movement, using their elegantly outstretched arms for balance. Sifakas other amazing creature features include a horizontally projecting set of lower front teeth used for grooming known as a “tooth comb” and a handy secondary tongue which helps keeps that tooth comb spic and span. Living in matriarchal social groups of three to ten animals, sifakas maintain contact with their troop known as a “conspiracy” through various vocalizations including the distinctive shi-fakh, shi-fakh sound from which this lemur species gets its name. Due to 90% loss of their forest habitat and increased hunting of culturally sacred lemurs for food, Coquerel’s sifakas have declined by more than 50% over the past 30 years. As of 2018, all nine sifaka species are listed by the IUCN as critically endangered. To learn how you can support conservation of the Coquerel’s sifaka and other lovable lemurs both in the U.S. and Madagascar, swing on over to the Duke University Lemur Center.

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Lisa S. French March 10, 2019

Leave it to Beavers

When it comes to naturally efficient ecosystem engineering, leave it to beavers. The largest rodents in North America, growing up to four feet long and weighing up to sixty pounds, these primarily nocturnal, web-footed, paddle-tailed dam builders help create the critical wetland habitats that 85% of all North American wildlife depend on for survival. When a beaver gets down to buck-toothed business, it can cut down as many as 200 softwood trees a year for food and dam building. It takes about five minutes for a beaver to chomp through the trunk of an 8-foot tree and about a week to build a 35-foot dam. These water barriers form ponds that protect the beaver colony from predators and provide underwater access to the family lodge, a dry, cozy den where males and females rest, nest and raise baby beavers, known as kits. Beaver-built ponds help to increase biodiversity by providing pooled water, plant life and shelter that attracts and supports creatures great and small including frogs, salmon, trout, ducks, heron, deer, and elk.

Beaver ponds also protect against a parched planet by trapping carbon, capturing rainfall and storing groundwater. Ranging in size from small woody clumps to 2,800-foot long mega-barriers, beaver dams contribute to water purification by filtering silt and pollution and capturing run-off from fertilizers. By transforming the landscape with their stick, stone and mud constructions these remarkable, semiaquatic ecosystem engineers create environmental benefits for wildlife, people and planet. Busy beavers indeed!

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Lisa S. French February 15, 2019

Night Pollinators

According to a report from the World Wildlife Fund, more than a third of crops globally are partially pollinated by animals. Lucky for us, these farmer’s helpers work around the clock. When busy bee and bird pollinators say goodbye to the day, night pollinators like the common fruit bat swoop in for the second shift. Bats pollinate over 500 species of plants including eucalyptus, mango, clove, cocoa, banana, and avocado.

In addition to helping keep humans stocked in delightful tropical fruits and all-important chocolate, these furry fliers play a critical role in maintaining the health and functioning of rainforest ecosystems. They can also contribute to natural reforestation of the tropics through “what goes in, must come out” seed dispersal. In case you were wondering, pollination by bats is called chiropterophily—chiro for hand, ptero for winged and phily as in tendency toward. Those of us with a tendency toward mangoes say keep up the good work little, wing-handed friends.

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Lisa S. French January 28, 2019

Beaked Builders

With his glossy blue-black plumage and striking violet eyes, the male satin bowerbird really stands out in a flock. As if purple peepers weren’t enough to grab attention, the bowerbird has evolved to develop quite a flair for design and construction in order to compete for female interest. And apparently, the competition is pretty stiff. Male bowerbirds are evaluated by females based on their ability to build a complex structure or bower made from twigs and dried grass. Once the walls of the U-shaped bower are complete, objects carefully chosen for artistic impact, including flowers, berries, shells, feathers and brightly colored bits of plastic, are precisely placed around the base of the bower to increase the overall appeal.

Bowerbirds that beautify with berries get the added advantage of a local crop to harvest from for redecorating when discarded fruits grow into plants. Native to Australia and New Guinea, each of the twenty species of these masters of avian architecture works with a species-specific color palette. To showcase his design chops, the satin bowerbird prefers to accessorize in shades of blue, perhaps as a complement to his feathered finery. If you’re still honing your decorating skills don’t worry, it took millions of years for the bowerbird to get this good. You can learn more about the satin bowerbird and other clever winged creatures in The Genius of Birds by Jennifer Ackerman.

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Lisa S. French January 24, 2019