Some world records provide a reason to celebrate. Not this one. It is estimated that in the late eighteenth century, carbon dioxide levels in the air would have been about 280 ppm (parts per million). Hawaii’s Mauna Loa Observatory has been measuring atmospheric carbon dioxide levels since 1958. The carbon dioxide reading from Mauna Loa that year was around 315 ppm. Last week, for the first time in millions of years, the carbon dioxide measurement at the observatory exceeded 400 ppm.
In both domestic settings and in the wild, instances in which animals take care of other species of animals have been noted with surprising frequency. What motivates animal-animal “adoptions?” Author Jenny Holland’s 2011 book, Unlikely Friendships, and a forthcoming sequel, Unlikely Loves, consider some of the possible explanations. Instinct might play a role, since the instinct to care for one’s own offspring is hardwired in mammals and necessary to perpetuate the parent’s genes. The parental instinct might be projected onto animals perceived to be juvenile, such as the captive apes that treated a house cat as if it were an infant ape. But other motivators could include social companionship, which many mammals require, or mutual benefit. More controversial is the notion that empathy, an emotion that humans often think of as strictly human, might be experienced by other animals as well.
In the New York TImes Science section Dana Jennings reviews a new book about snakes. “Serpentine,” by Mark Laita, takes the reader on a whirlwind tour of snakes on every continent except Antarctica. Combining stunning color photography with fascinating facts, this book might just pry open some closed minds about snakes.
Finding fossilized bones from millions of years ago is difficult enough, but a recent analysis of the body’s tiniest bones, ossicles from the middle ear, is remarkable. In this case, the ossicles are from Paranthropus robustus, which lived about 2 million years ago and Australopithecus africanus which lived 23 million years ago. Even though both hominids were separated by many years of evolution, the malleus, another small middle ear bone, in both was “humanlike.” Palaeoanthropologist Rolf Quam of Binghamton University believes that these small ear bones suggest an evolutionary link to modern humans and may even implicate the foundation of human hearing that would eventually be attuned for speech. Other anthropologists disagree, and maintain that few if any fair inferences can be drawn from the shape of these tiny bones.
No, it’s not another zombie cult movie. Osedax worms are just another example of how nature fills every niche. When whales die, their bones retain nutrients locked inside of hard calcium formations. Exploiting that resource is the Osedax worm. This bizarre mouthless creature uses secreted acid to dissolve the calcium and burrow inside the whale bones. Once inside, the female dines on the nutrients inside the bones and also lays eggs, which are fertilized by the dwarf male Osedax which is just a fraction of the female’s size.
Our studies of vertebrates may have shortchanged the largest vertebrate group: fish. Richard Broughton, associate professor of biology at the University of Oklahoma, is helping to close that gap. He has published two studies that offer a new look at the evolution of fish species, and has created a new fish tree of life. The fish tree is a collaboration of Broughton and other scientists as well as the National Science Foundation.
An Israeli study sponsored by the European Centre for Disease Prevention and Control in
Stockholm has examined the incidence of West Nile virus infections in Europe and has concluded that warmer average temperatures have caused mosquito populations to spread West Nile virus to areas of Europe that were never before infected. The virus begins in infected birds which are bitten by mosquitos that in turn bite humans, thereby transmitting the disease. Once infected, West Nile victims, especially those with compromised immune systems, can suffer irreversible brain damage. According to the study, increased temperatures, even more than increased humidity, benefits the West Nile virus.
Wind turbine electricity generation has been rightfully hailed by environmentalists as a limitless source of clean energy. Unfortunately, the early designers of wind turbines never took into proper account the many birds that would be killed by the turbines’ powerful blades. It is estimated that half a million birds and bats are killed by wind turbines every year—in one particularly deadly Oregon wind farm alone, 10,000 birds are killed each year. Steps are being taken to address the problem. For example, new designs eliminate the early latticework of some turbines that actually attract birds. Moreover, future wind farms ought to avoid locations that are known to be migratory bird routes. So far, a 50% reduction in bird deaths has been achieved in one location by implementing measures like these.
It has been well documented that the persistent and widespread use of antibiotics over the past decades has led to the proliferation of dangerous drug-resistant bacteria. As medical science begins to run out of options, a new strategy is starting to take shape. The fact is, even the nastiest drug-resistant bacteria have enemies. Predatory bacteria, bacteria that attack other bacteria but not human cells, are being spotlighted as a possible new avenue to fight fire with fire. So far, predatory bacteria have successfully killed off large number of harmful bacteria in laboratory studies. Animal trials will begin soon.
It is well known that female black widow spiders, among other arachnids and some insects, will often devour their male companion after mating. From an evolutionary perspective, this is logical since the female gets a free meal and the male will pass on its genes, albeit posthumously. But recent research shows that in a few species of spiders, the male sometimes will devour the female. This, of course, makes less sense. Scientists are looking for the motivation behind this strange behavior in at least one spider, Micaria sociabilis. So far, they propose that since the behavior only seems to take place some 20% of the time, it could simply reflect the male’s brutal change of mind about the pairing, a sort of divorce spider-style.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
On the heels of recent news that readily available 3D printers and computer software can be used to manufacture firearms at home, New York Times reporter Andrew Pollack discusses another controversial cottage industry synthetic biology. The goals of the amateur group in this case appear sanguine: to produce plants that glow in the dark courtesy of an implantable gene from bioluminescent marine plants. The group already has raised money online, and is embarking on gene transplantation, the cost of which has been reduced to the hobbyist level by technological advances. Despite the allure of trees that light the street at night, two environmental organization have already petitioned the Agriculture Department to shut down the hobbyists. However, jurisdiction is unclear as, once again, the pace of scientific and technological advances is far ahead of the law.
Gunflint bacteria, first discovered in 1953, lived almost 2 billion years ago in the seas of a relatively young earth. But it wasn’t alone. New techniques for 3D imaging of fossilized bacteria such as gunflint trapped in ancient rock have revealed that other bacteria fed on the gunflint and that process of decay probably produced a pervasive rotten-egg stench across the planet. A byproduct of this decay would have been free carbon dioxide, which would have been released into the atmosphere, thereby providing food for photosynthesizing plants and algae. This, scientists believe, was earth’s early and very smelly cycle of life.
A Canadian biologist named Alexandra Morton is at the center of a controversy over the spread of infectious salmon anemia (ISA). The disease can cause devastation among farmed salmon, and has taken its toll in Chile. Morton believes that the disease is already infecting the wild salmon populations of the Pacific Northwest. However, the scientific establishment in Canada and the United States has rebuffed Morton’s conclusion and insists that there is no convincing evidence that the disease is present in wild salmon. No doubt stoking the controversy is the long standing criticism that salmon farms tend to be overcrowded and breed diseases, such as the viral ISA, which can spread to wild salmon. Whoever is right, extra vigilance would be wise; ISA can destroy some 90% of the salmon farm population.
Traditionally, human and veterinary medicine do not have many points of interconnection, and that might be a mistake according to Dr. Barbara Natterson Horowitz. Ten years ago, she began consulting with the Los Angeles Zoo, and that experience started her thinking about the many intersections between human and animal disease. Her book, Zoobiquity: The Astonishing Connection Between Human and Animal Health, explores some fascinating similarities and differences between human and animal disease. For example, animal studies have suggested that animals and humans are equipped with not just a flight or fight response to danger, but also a faint response, which, as every opossum knows, also can save your life.
In 1853, when the oceans were not so polluted and acidified, Leopold Blaschka, a glassmaker, became enchanted with the more delicate forms of sea life: jellyfish, anemones and octopi. He and his son began to create a unique and exquisite glass menagerie of sea creatures. In the end, they created hundreds of glass models. Writing in the New York Times, marine biologist C. Drew Harvell of Cornell University describes her efforts to locate the real-life sea creatures which inspired these glass models. Harvell’s expedition takes place in Hawaii and combines stunning underwater videography, a lost art of glass craftsmanship and the scientific quest to document how many of these once common sea creatures are still common today.
Right now in the United States, there are an estimated 6 million feral pigs. They are in almost every state, but California, Texas and Florida have the lion’s share. Wildlife News reporter Ralph Maughan discusses the many diseases that these pigs can transmit to humans, from anthrax to salmonella, and how difficult they are to control because of their impressive intelligence. They multiply quickly and their appetites and large size have put significant competitive pressure on local plant and animal populations. Public awareness, outside of hunters, seems to be limited because of scant press coverage. As Maughan puts it: “There is a lot of irony that perhaps 1500 wild wolves in the West causes a huge political stir despite effects that are hard to document, while 6million hogs ripping up the ground is hard to get public attention.”
The sugary nectar of flowers attract many admirers from bees to hummingbirds. But some species of bats have also developed a taste for sweet nectar, along with a special mechanism for getting to it. A study of one such species, Glossophaga soricina, reveals that the bat has a specialized tongue that becomes thinner and longer when a sweet smelling flower is within reach. The bat’s tongue then enlists tiny hairlike papillae that become hydraulically swollen and provide a dramatically increased surface area to the tongue in order to slurp up the flower’s nectar. The entire process takes just a fraction of a second. Honey bees and hummingbirds use different tongue structures to extract nectar, but researchers believe that the bat’s method is not unique and is probably employed in some form by other animals.
The media has fostered an automatic mental association between dinosaurs and very large animals. However, that may be only half the picture. In Canada, an 85 million-year-old fossil of a dog-sized dinosaur called Acrotholus suggests that some revision is necessary. Acrotholus had a thick domed head, which not surprisingly is the only part of it that survived fossilization. David Evans of the Royal Ontario Museum believes that the world once teemed with many types of smaller dinosaurs, but that they are underrepresented in the fossil record because their smaller bones did not fossilize as well as did giant dinosaurs. Indeed, the very absence of small dinosaur fossils outside of the thick domed Acrotholus, suggests that the supposed lack of small dinosaur diversity may be illusory. Although we will likely never know what has been lost forever, Evans cautions that we ought to be careful about the conclusions we draw from what is probably a partial fossil record.
Tectonic plates are separations in the earth’s crust that move slowly and sometimes collide causing earthquakes. Martin Van Kranendonk of the University of New South Wales and Christopher Kirkland of the Geological Survey of Western Australia wanted to find out the history of plate tectonics on earth. By studying rare elements in rock samples and measuring oxygen isotope levels, researchers have concluded that the earth has been tectonically active for at least 3 billion years. It those early years, the intense heat and resulting softer crust may have minimized tectonic collisions. However, the evidence suggests that the most active period for plate tectonics was 1.1 billion years ago when all of the continents collided and formed a single supercontinent. Since then, a gradual reduction of activity has occurred, as the earth ages and continues to cool internally.
This summer, the east coast will be inundated by masses of cicadas from “Brood II,” who will end their 17 year underground existence and come to the surface to breed. Although there are six other cicada groups in the United States, each tied to its own 13 or 17 year life cycle, the insects seems to trace back to a common ancestor some 8,000 years ago. Entomologists believe that the cicadas’ separate broods formed as the result of dramatic climate warming following the last ice age. If this is the case, any new dramatic climate changes that affect the insects might be reflected in a new change in their heretofore predictable life cycles. Entomologist Craig Gibbs recently put it this way: “the cicada may yet reprise its role as climate indicator if its cycle is disrupted by a warming planet.”
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
Think you understand your cat? Global Animal offers several explanations for common but still bizarre cat behaviors and antics. For example, if you’ve wondered why your cat insists on following you into the bathroom, consider that from its perspective, you are now a captive audience in a small space.
St. Augustine Alligator Farm and Zoological Park has a new Komodo dragon. Named Tujah, which means “seven” in the local Indonesian language, he is eight feet long. Komodo dragons are voracious eaters. They can eat up to 90% of their body weight in one sitting. When Tujah was released into his new outdoor home for the first time, he flicked his tongue in order to sniff every corner of the large enclosure. He also quickly found two quails that were placed there as a sort of housewarming gift. Precautions against being bitten are extremely important for human visitors and handlers since Komodo dragons kill their prey by infecting them with a menagerie of bacteria. If all goes well, in October Tujah will be introduced to a female Komodo dragon who has already been chosen for him.
In what appears to be a scientific first, Uruguayan scientists have successfully implanted “fluorescent” genes from an Aequorea jellyfish into nine sheep. The lambs are developing normally, however, when they are exposed to ultraviolet lights, their skin glows a green color. Although this particular genetic reconfiguration would appear to have little practical value, researchers see this as a step toward introducing genes into sheep that can cause them to secrete into their milk chemicals useful to humans.
By 1972, scientists knew that many species of marine mammals were in serious trouble, some facing extinction. Congress was able to come together and pass the Marine Mammal Protection Act (MMPA), which was supported by then president Nixon, and which protected many species of marine mammals. Now, 40 years later, it appears that the MMPA has paid dividends. In a new report, scientists believe that the MMPA has allowed “countless tens of thousands” of sea lions, seals, whales and dolphins to recover to where they now live in sustainable populations. Some sea mammals,such as the right whale, are still critically endangered, but at least are still with us. New challenges, including sonar noise and shipping lanes that overlap whale habitat, will require amendments to the act, but that will require the present Congress to muster the political will it did in 1972.
Coral are living sea animals that feed on algae. Day and night, the tops of one species of coral, xeniid corals, can be seen pulsating opening and closing as if breathing. Maya Kremien of Hebrew University of Jerusalem has studied this coral and has concluded that this activity has several purposes. First, because they are so dependent on algae, it is important for coral to keep algae growing at a peak rate. But the oxygenation of the water, a byproduct of photosynthesis of algae, puts a natural brake on algae growth. Enter the coral. By pulsating the water, these animals disperse excess oxygen and hence make the conditions more optimal for the algae. In addition, pulsation confers another advantage which is to improve nutrient supplies by pumping in fresh seawater.
The United States is the proud home of what are believed to be the world’s oldest trees. In California, the previous champ, but now #2, is “Methuselah,” a 4,845-year-old Great Basin bristle cone pine. But recently a new champ was crowned, also in California’s White Mountains. It’s estimated age is an astonishing 5,062-years-old. Around the world there are other very old trees. In Iran, a 4,000-year-old Cypress is considered the oldest tree in Asia. In North Wales, England there is a 4,000-year-old Yew and in Chile there exists a 3,642-year-old Patagonian cypress.
Scientists have long puzzled over why almost all the amino acids that make up life on earth have a left-handed and not a right-handed structure. Nature, it would seem, ought to have no particular preference. One new theory looks to the stars. It takes advantage of a recent observation that light from one nebula where many new stars in our galaxy are born exhibits “circular polarization.” That means light from this nebula twists like a corkscrew in one direction more often than it does in the opposite direction. Polarized light can cause molecules, such as amino acids, which are also formed during the birth of stars, to skew toward left-handedness. The theory suggests that these biased amino acids, formed by polarized light, were carried to earth by space rocks and might have seeded the planet with left-handed amino acids, a bias that remains with us today. Scientists are now looking for additional examples of circular polarization in our galaxy to help confirm their findings.
The Manx shearwater is a seabird that breeds in Great Britain but migrates thousands of miles every year to South America during the winter. In order to get better information about exactly what the bird is doing during it hiatus in the Southern Hemisphere, scientists fit the birds with “miniature geo-locators and lightweight GPS loggers.” Using this new computerized system (called ‘etho-informatics’) over the past three years, University of Oxford researchers now have huge amounts of data. For the most part, the shearwater seems to spend its winters off the coast of Brazil doing what people do resting up before they embark on a busy new breeding season back home.
For people, especially daters, body language is a complementary form of human communication. But elephant expert Joyce Poole, who has been studying elephants for decades, believes that elephants have their own body language, and that it is just as robust and meaningful as anything humans demonstrate. In this National Geographic article, Joyce explains how elephants use movement, gestures and posturing to communicate meaning to other elephants and how they even employ pratfalls to amuse humans.
In the forests of Madagascar the dwarf lemur has developed a unique form of hibernation. Unlike cold temperature hibernators who need to hibernate to survive a harsh winter, the dwarf lemurs hibernate in order to survive a cool, dry season in the tropics, where food becomes scarce. Before going into hibernation, the dwarf lemur gorges itself on available food. It then hides in a tree hollow or in the ground and goes into an ultra-deep sleep. And, unlike ordinary hibernators, it does not let its body temperature plummet, but rather matches it to the existing local conditions, allowing it to fluctuate as much as 20 degrees C. Most of the lemur’s stored up fat is in its tail, and that becomes its source of nutrition during the hibernation period.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
New evidence might help settle a scientific argument over whether dinosaurs sat on their eggs like birds, or took a more reptilian approach and left them in the ground to hatch, as do crocodiles. After studying numerous fossilized dinosaur clutches of eggs, as well as determining the porosity of the egg shells, University of Calgary dinosaur researcher Darla Zelenitsky and Montana State University paleontologist David Varricchio have concluded that in at least one dinosaur species, the eggs were half-buried in the soil and the upper half was incubated by the warmth of the sitting dinosaur parent.
The leatherback turtle is the largest existing turtle; at maturity, they weigh in at around 200 pounds. An area of Puerto Rico known as the Northeast Ecological Corridor, which contains beaches and vegetation, has recently been named a federally protected area because it is a nesting grounds for the leatherback. Last summer, developers using heavy machinery crushed thousands of leatherback turtle eggs and hatchlings in the process of moving sand. This latest round in a political fight between building developers and environmentalists has gone to the environmentalists, but developers have not given up on projects such as golf courses and hotels that would severely threaten the leatherbacks.
Whether or not you enjoy escargot, this gigantic invasive snail species that is becoming a new threat to south Florida is not on your menu. The snails are from eastern Africa and have arrived in Florida by the exotic pet trade route and accidentally in shipments of produce. Experts call them a “trifecta” threat. Not only do they eat enormous volumes of agricultural produce, but they also chomp down on plaster and stucco thereby threatening property, and they carry a form of meningitis virus, that is a public health threat. An aggressive campaign to root out the snails is underway in the hope that they can be controlled before they invade further north.
Drought conditions in the United States have threatened forests as well as agriculture. When trees are in distress because of insufficient groundwater, the mechanism by which they move water up from the ground can make sounds that can alert experts that emergency measures are needed. Water molecules attract each other and it is this fundamental law that permits trees to coax water up in columns against gravity into the highest portions of the treetops. However, when the groundwater becomes inadequate, the columns of connected water inside the trees become disturbed and air bubbles form. The air bubbles give off a distinct noise pattern, called cavitations, which can be picked up with a microphone. This discovery may be the face of future forest service protections microphoned trees that will tell officials when the effects of drought are beginning to do actual harm to a forest.
South African Kevin Richardson has reared 27 adult lions from young animals. In this interview, he explains his philosophy of raising and living among lions as if he were a member of the pride. In 15 years of doing this work, he has suffered only minor injuries. Richardson would never attempt an interaction with a dangerous wild animal and he insists that you must give lions a wide berth when they are having a “bad day.” Words to live by.
Around 150 years ago, a zoologist named Joel Allen proposed a rule of evolution. He postulated that when species adapt to cold climates, there are changes not only in the thickness of their fur, their rate of blood circulation and their metabolism, but also in their morphology, or body shape. According to Allen’s theory, cold climate species develop short limbs and thick bodies (think polar bears). This is an example of evolution complying with the laws of physics—a larger mass to surface ratio means that less energy must be expended to keep that body warm. Interestingly, the effect is not only genetic. In a single generation, mice exposed to artificially low ambient temperatures developed more stunted limbs than their counterparts who were given warmer environs.
Not long ago, the coelacanth was thought to have gone extinct until a live specimen was found in a South African fish market in 1938. The coelacanth is believed to be an ancient pioneering species that hundreds of millions of years ago grew limbs and made the transition from the sea to the land, thus harkening the beginning of complex land-based animals, including humans. Coelacanth DNA has been sequenced and reveals more similarity to human DNA than does other fish DNA, with the exception of the lungfish, which DNA is even closer. In a new experiment, coelacanth genes that exist in animals but not in other fish were isolated. When those genes were implanted into mouse DNA, the affected mice began to grow new limbs.
A research team from the University of Colorado at Boulder, studied the bacterial colonies on human skin and dog fur of 159 people who live in families with a dog. What surprised scientists was just how much dog bacteria is shared with the humans in their families. Associate Professor Rob Knight noted, “In fact, the microbial connection seems to be stronger between parents and family dogs than between parents and their children.” But it seems that this inter-species sharing may actually be healthful.
If you were to ask the average person what people have in common with the zebrafish, the most common response would be “very little.” However, that is not the case. Two studies from the Wellcome Trust Sanger Institute reveal that sequencing the zebrafish DNA has taught us that 70% of human proteincoding genes are also found in the zebrafish genome, as well as 84% of genes implicated in human disease. In addition, by deliberately creating genetic errors in zebrafish, scientists have already isolated the genes involved in several human diseases, including cancers.
When it comes to nature, function trumps fashion. Take a look at some of the strangest looking headgear that you’ll ever see on a living creature. From banana-nosed protrusions that are used to detect electromagnetic fields to fish that wear their own fishing rod and lure on their heads, this edition of the fishery blog is both entertaining and educational.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
Clifford Ray, a former basketball player for the Golden State Warriors, once used his exceptionally long reach to save a dolphin. It was in 1978 that a Marine World bottlenose dolphin known as “Doctor Spock,” had swallowed a large metal bolt. To avoid surgery, marine animal experts sought out someone with exceptionally long arms, and that is when Ray got the call. Using his 45” reach, Ray thrust his arm into Dr. Spock’s stomach, actually dolphins have two stomachs, until he felt and removed the metal bolt. Even more amazingly, the unanesthetized Mr. Spock calmly endured the ordeal and did not bite Ray. Years later, when Ray visited Marine World, Mr. Spock always seemed to acknowledge him almost by way of a thank you.
In Mongolia, the great bustard is probably the world’s heaviest flying animal. The male birds can weigh in at over 30 pounds. They also take a different approach to migrating. Rather than flying thousands of miles with few stops, these beefy birds take four months to travel thousands of miles while migrating from Mongolia to the southern Chinese provinces when the weather gets colder. They conserve energy by spending as little as 2% of that time actually in the air. Making frequent stops for food and rest, the great bustard take the slow and steady approach to migration.
It is the stuff of bad dreams. A newly discovered tarantula-like species, Poecilotheria rajaei is related to the “tiger spiders” of the region. It has a total leg span of over 8 inches the size of a human face and, unlike most tarantulas, is highly venomous. The creatures are native to the forests of Sri Lanka and are brightly colored with stripes, hence the moniker, tiger spider. Because of deforestation in the northern Sri Lanka forests where these arachnids live, they are disappearing and are starting to inhabit old buildings as a substitute for the missing trees. While the taxonomy suggests that this new discovery is a separate species, confirmatory DNA testing will be done shortly.
Move over honey bees, a honeyproducing wasp is being studied in south Texas. Scientists from the London Zoo are zeroing in on this unusual species, known as the Mexican honey wasp, in an effort to understand the behavior and honey producing capabilities of this much overlooked insect. Although the quarter-inch individuals are small for wasps, their nests are enormous at 4 feet wide. They can contain some 20,000 wasps and 3,000 queens. In South America, the wasp’s honey is farmed but in Texas, little is known about the particular kinds of flowers the wasps visit and pollinate. An important offshoot of the research concerns the development of new pesticides that are friendly to social insects such as wasps and honey bees. Today’s pesticides are strongly suspected in the spread of colony collapse disorder in honey bee populations in the United States.
Off the coast of Oregon and California, Stanford University scientists studying purple sea urchins, have been surprised at the animal’s viability under acidic ocean conditions. Sea urchins are ancient, and may have survived in one form or another mass extinctions that wiped out more complex and less adaptable species. DNA analysis shows that the sea urchin’s genetic toolkit contains a grabbag of genes: some that can favor acidic environments as well as those that favor the opposite. By hedging its genetic bets, so to speak, the sea urchin might be one species of animal that will perhaps once again survive where other species perish.
Michael Blaber, a professor in Florida State’s College of Medicine, is pioneering a new theory about the earliest emergence of life on earth billions of years ago. Most current theories posit that the most likely component of life first to have formed from available prebiotic molecules was RNA. But according to Professor Blaber’s research, the ten amino acids that were likely present on earth before life began would have needed a high-salt environment in order to fold into the proteins that began life’s processes on a microscopic level. So far, using as few as 12 amino acids out the 20 which are used by all life forms today, Blaber has been able to successfully create folded proteins. If his team can achieve foldable proteins with only the ten naturally occurring amino acids, he will have the proof he needs.
700 years ago, New Zealand’s giant moas vanished, the consequence of extensive hunting by the native population. Scientists studying moa fossils today are puzzling over what appears to be an extreme example of sexual dimorphism the size difference between male and female of the same species. In humans, sexual dimorphism is relatively minimal, but in the giant moa, it was extreme. Based upon the fossil evidence, the female moas were three times the size of the males.
As President Obama opens an initiative on brain science research, a new technique developed at Stanford University in California may be a game changer. By injecting a series of chemicals into dead mouse brains, the researchers have been able to create a nearly transparent brain that has all of the brains proteins, RNA and DNA still intact. The gel-like brain that results leaves the neurons in place, as well as interconnecting structures called axons. The technique will have to be improved in order to work more effectively on the human brain which is of course much larger and requires the dissolution of many more fatty lipids to achieve transparency.
It has been long understood that fish living in dark cave waters will eventually evolve into sightless, eyeless fish. But researchers were surprised to learn after experimentation that the same fish also seemed to have major hearing deficits when compared to surface fish. At high frequencies, the cavefish heard virtually no sounds and it appears that they are missing one third of the hair cells needed for hearing that are present in surface fish. One theory explaining the loss of hearing centers on the fact that cave background noise also tends to be in the higher frequencies. Whether this hearing deficit is an adaptation to filter out noise or whether some other phenomenon is at work will most likely be determined when other blind cave dwelling species also have their hearing tested.
Only 2% of the original Brazil’s Northeastern Atlantic Forest remains today. Logging, clear-cutting and fires have destroyed the rest. In all likelihood, one of the forest’s denizens, a porcupine new to science, would have vanished before it was ever recognized as a new species. However, scientists have found the new porcupine in an isolated and preserved patch of the forest. They have named it Coendou speratus, a combination of its local name and the Latin word for “hope.” The porcupine is a tree-lover and climbs up and down the forest trees in search of seeds. The lead researcher aptly summed up the situation: “Given the rate of destruction in this area, where 98 percent of the original Northeastern Atlantic Forest has already been destroyed, imagine how many species could have gone extinct before we even knew about them.”
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
It is becoming more obvious to the medical community that the billions of bacteria that line our intestines are also determined in part by genetics. By luck of the draw, some people have the type of bacteria that are tremendously efficient at utilizing every last calorie. Others have species of bacteria that are less efficient and waste more nutrients. If you’re in the former category you will probably put on the pounds faster than those with the less efficient bacteria. It is so far unclear how much genetics and environment each contribute to who gets which and whether interventions short of bariatric surgery can permanently change the bacterial population balance for individuals.
The ability to fly, or at least glide, must have distinct survival advantages since it developed independently in so many animals. In Malaysia and Borneo, Wallace’s frog, named for British scientist Alfred Russel Wallace in the 19th century, has developed the ability to parachute out of the trees it calls home and glide for as much as 50 feet to another tree or even onto the ground. The frog has oversized webbing between its toes which give it aerodynamic lift and thick foot pads to give it a soft landing.
With only a few hundred thousands neurons for a brain, it is hard to understand how individual ants act collectively to find the shortest path to their nests and accomplish other tasks that would seem to require much more intelligence. Scientists believe the ants use simple local rules to navigate. For example, when an ant comes to a fork in the road it follows the pheromones left by its peers, but it also is programmed to take the path that deviates the least from the path it was following to the nest. Using sugar-cube sized robots that follow trails of light left by other robots, scientists have noticed that these robots, too, eventually “learn” to take the path of least divergence in completing a maze. Complex behavior arising from simple rules is an important concept that has application for problems as diverse as computer communication and long distance trucking routes.
Coming in swarms of biblical proportions, Magicicada septendecim, otherwise known as the cicada insect, is about to emerge again on the east coast. Different broods of cicadas hibernate underground for either 13 or 17 years and then reemerge, en masse, in the millions as part of a bizarre life cycle. The east coast brood, known as brood 2, covers an area from Connecticut to North Carolina. Last awaking in 1996, they are scheduled to take over trees everywhere in their range as soon as the ground temperature reaches 64 degree Fahrenheit. Millions of cicadas have been known to take over a single acre of land. And if you’re wondering how nature came by the 13 and 17 year intervals think prime numbers. One theory suggests that mathematically, parasites with two-year life cycles would not be able to infect the 17 year cicada more than twice a century.
It’s an ideal situation for stowaways. Ocean going commercial vessels fill their ballast tanks in one far-flung port and empty them in another. Along for the ride are any number of hitchhiking creatures that enter the ship along with its ballast water. It was just such a mechanism that allowed comb jellyfish from North America to invade the Black Sea and cause a cataclysmic decline in native marine life there. It would seem that a United Nations treaty requiring all international vessels to treat their ballast water would be a reasonable solution. So far, however, the United Nations has declined to act and even powerful countries such as the United States have done little to address the issue.
Hundreds of millions of years worth of success has honed the dragonfly into an expert aerial hunter. With a hunting success rate of around 95%, the dragonfly puts to shame other predators many of which fail as often as they succeed in bringing down their prey. The amazing ability of a dragonfly to zero in on its flying target, predict the target’s future path and then intercept it and eat it in midair is orchestrated by a relatively small but dedicated number of neurons that direct a 360 degree visual system. Entomologists are not alone in their fascination with dragonflies. Military experts would love to duplicate the dragonfly’s targeting and interception abilities.
Large parts of Lake Erie are turning green, a situation that spells major problems for the local ecology. The problem is a primitive life form called cyanobacteria, also known as blue-green algae. The ultimate cause is a change in local agricultural practices. Farmers now fertilize earlier, and with greater amounts of fertilizer#&8212;a practice that almost insures that extra fertilizer runoff will find its way into the lake. Once the fertilizers make their way into Lake Erie, the cyanobacteria feast and multiply. In the process, the decaying bacterial organisms deplete the lake of oxygen and release toxins, both of which in turn kills fish and other aquatic life. Dead zones, areas where no life exists, will result. If there is any good news it is that agricultural practices can quickly change and eventually reverse the damage.
Duplicating the stickiness of gecko feet has been an aspirational goal for applied science looking for a better adhesive under wet conditions. In a study of the tiny hairs that give the gecko its excellent velcro-like grip, scientists have noted that the grip depends on the “wettability” of the surface upon which the grip is maintained. Surfaces such as glass have a high wettability index and therefore even gecko grips are weakened on them. On the other hand, hydrophobic surfaces, such as waxy leaves and tree bark, allow a firm grip even when covered with water, such as during a tropical forest downpour.
At the Long Marine Lab at the University of California, Santa Cruz, Ronan, a three-year-old sea lion has proven her ability to bob her head with the beat of various music. Previously, only humans and birds were known to have the ability to keep a beat. However, Ronan can change her moves to suit apparently any beat and demonstrates this in the video. Enjoy.
An American bird known as the Gunnison sagegrouse may be the most endangered bird species in the country. It was discovered only 13 years ago but only an estimated 5,000 animals exist today in a limited range in Colorado. The male bird’s unusual courting ritual involves inflatable yellow chest sacs that make popping noises while the bird struts its flamboyant spiny tail feathers. Now the race is on to see whether the bird will become extinct before it makes it through the red tape and delay required to become a classified endangered species.
More at Discovery News.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
A species of Australian frog known as a “gastric-brooding frog” had a strange method of bearing its offspring. It swallowed its fertilized eggs, hatched them in its stomach, and finally gave birth by spitting the newborns out of its mouth. The frog became extinct in 1983. Now the “lazarus project,” led by a team of University of New South Wales scientists, is attempting a de-extinction event. Although so far unsuccessful, scientists are using stored DNA from the extinct frog and placing it into the emptied nucleus of an egg from a related frog species. They expect that the obstacles to cloning the extinct frog are more “technical” than biological and that a living cloned gastricbrooding frog will be resurrected soon.
Author Virginia Morell’s new book entitled, “Animal Wise: The Thoughts and Emotions of Our Fellow Creatures,” captures some of the many ways that animal behavior parallels human behavior. The book covers the surprisingly large vocabulary of dogs, the slapstick humor of rats and the amazing verbal intelligence of many birds. Even insects get their due, as Morell describes ants building their precisely measured colonies like miniature carpenters who measure twice and cut once.
In the Marianas Trench in the Pacific Ocean, the deepest spot on the earth’s surface at a depth of some 36,000 feet, microbial life flourishes. At this depth, there is no sunlight and the water pressure is 1,100 times what it is at the surface. Nevertheless, these conditions are ideal for the countless bacteria and other microbes that make this “extreme” environment their home. Ronnie Glud of the University of Southern Denmark led a team of scientists who found that dead plant and animal matter that drifted down into the trench formed a perfect food source for bacteria and other microbes.
Darren Naish recounts his investigation into an “old world” cat—a feline species extant in Egypt and Asia but today largely disappeared from Europe. The jungle cat or swamp cat is an undomesticated feline that is larger than a domestic cat. In England, escaped specimens can be rarely found in the countryside where they prey on rabbits and rodents. They also can breed with domestic cats and hybrid species are known to exist, which are fertile. The last time the jungle cat was endemic to Britain was in the Pleistocene Epoch which lasted about 2 and a half million years, ending around 11,500 years ago.
An experiment with roosters conducted at Nagoya University in Japan has found that a rooster’s predawn crowing is based on its internal clock rather than external stimuli. In the experiment, roosters were exposed to 12 daylight hours and 12 dim light hours in one experiment and to 24 hours of dim light in another. In both cases, the roosters crowed at dawn or two hours before dawn. When the scientists added external stimuli such as light and sound, the roosters still responded predominantly to their own internal clock, which tells them when it is dawn. Interestingly, hierarchy plays a role in which roosters crows the earliest, with the highest ranking roosters getting that honor while the lower ranking members wait their turn.
A new genetically modified food comes in the form of tomatoes that have been engineered to produce a peptide that acts like a “good” cholesterol. Simply eating the tomatoes releases the peptide into the small intestine where it it takes on the functional characteristics of high-density lipoprotein or good cholesterol. One of the hopes of the research is that the antii-nflammatory effect of the peptides will alleviate conditions such as Alzheimer’s disease, as well as other chronic inflammatory diseases.
If you are a sea snake and consume large spiny fish, a big head with a large mouth would seem the correct evolutionary choice. Why, then, are some sea snake’s heads getting smaller and smaller? Dr Kate Sanders from the University of Adelaide along with other researchers have been studying this riddle and they may have an answer. When the local food choice involves pushing a snake’s head into a narrow burrow to find a tasty treat, then it pays to have a small head in fact, the smaller the better. Two sea snakes, “the bluebanded sea snake (Hydrophis cyanocinctus) and the slender-necked sea snake (Hydrophis melanocephalus) were almost indistinguishable genetically,” but the latter had developed a much smaller head. Evolutionarily speaking, this suggests an example of ongoing speciation in which two members of the same species change over time to become separate species.
More at Science Daily.
In the Cayman Islands a burgeoning tourist attraction is swimming alongside the stingrays in the blue waters of the Caribbean. It is estimated that each stingray produces some $500,000 in annual tourism revenue for the island. The tourists also enjoy feeding the stingrays, which is where the story gets complicated. Scientists have compared stingray populations that have become habituated to human interaction and feeding with separate populations that have had little human contact. They found pronounced behavioral differences between the two groups. The tourist-acclimated stingrays changed from night hunters to day feeders and also lost their natural sense of individualism, learning to swim “fin to fin” together to enjoy the bounty provided by the tourists. Scientists warn that these kind of rapid behavioral changes can be detrimental to the stingrays in the long run and urge moderation of the feeding routines.
Dr. Svante Pääbo and colleagues have presented a draft version of the Neanderthal genome this one the most complete to date. The highquality genome sequencing was completed using a small toe bone found in a cave in Southern Siberia in 2010. The cave where the fossils were found borders Russia, China, Mongolia and Kazakhstan and was occupied not only by our Neanderthal cousins but also by Denisovans, still another cousin on the growing list of ancient human relatives.
A new experiment seems to bolster evidence that mammals, including humans, use scent as a means of choosing a mate. Immune systems between individuals differ and it makes genetic sense to choose a mate with an immune system different from your own so as to increase the odds that your offspring will have a fuller immune arsenal. Researchers from the University of Tübingen’s Immunology department and the Proteome Center have found that mice can detect MHC (major histocompatibility complex) genes, which inform about an individual’s immune system. Different MHC peptides on cell surfaces of mice give off distinct scents and mice have special smell sensor cells that can distinguish among them. In the experiment, high concentrations of synthetic MHC peptides actually influenced the behavior of the test mice. So far, a similar system for humans has not been detected, but experimenters think it likely exists in some form.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
Of course, a flower is optimized to attract bees for pollination, but scientists recently discovered that in some flowering plants it is the caffeine in the nectar that seals the deal. Coffee and citrus flowers that contain caffeine are much more likely to be remembered by bees than flowers without caffeine. The theory is that caffeine acts on bees in a manner similar to humans it enhances alertness and memory. Bees that just feasted on caffeine-loaded nectar are more likely to remember the location and physical attributes of that flower and return to it.
In 2009, a Bengal tiger cub in India was orphaned when his mother disappeared, possibly killed. Zookeepers at the Bor Wildlife Sanctuary raised the cub, named him Bhangaram and hoped to release him into the wild once he reached adulthood. When that day came recently, the zookeepers decided to develop hunting skills for Bhangaram, which he never had a chance to learn from his mother. They released a goat into his enclosure, hoping his instincts would take over and he would make a quick kill. Instead, the tamed tiger befriended the goat and played with it for two days, showing no intention of eating it despite being hungry. Apparently, the window to learn hunting skills closed on Bhangaram. Conservationists caution that however charming this story may appear, it is one more small catastrophe for wild tigers whose world population has plummeted almost 97% in the past twenty years.
Although extinct today, the Falkland Islands Wolf was a mystery to 17th-century explorers and scientists who wondered how this solitary mammal found its way there when even rodents did not. At one time it was hypothesized that the wolf was brought to the Falklands by humans in a semi-domesticated state. However, it appears that the solution is a more natural one. At the height of the last glacial period between 18,000 and 25,000 years ago, the strait separating the Falklands from the Argentine mainland would periodically freeze over. Wolves from the mainland, in search of seals, penguins and water birds, crossed over the frozen strait and eventually made the Falklands their home.
There is a consensus in the scientific community that at least some extinct species can technically be brought back through cloning techniques. However, critics have decried the significant expense of such efforts and have questioned whether or not we can ethically justify experimenting with individual clones, which may have little or no chance of natural re-population now that their habitats are gone. In this article from National Geographic, several scientists provide short opinion video clips and explore the pros and cons of “de-extinction.”
The giant tortoises of the Galapagos Islands don’t move very fast and they don’t go very far. However, new research shows that they nevertheless do migrate if only a few miles. Stephen Blake, a researcher at Max Planck Institute in Germany tracked the tortoises and discovered that they graze on grass in the highlands of Santa Cruz Island in the Galapagos and slowly migrate to the lowlands in December, which is the start of the rainy season. Although no match for the land migrating record holder, the caribou, which migrates 700 miles, and not even close to birds, which circumnavigate the globe, the discovery that these tortoises do in fact migrate is a scientific first.
The California Condor is an endangered species. In the 1980s, fewer than two dozen wild birds remained. Today, thanks in part to conservation efforts by the San Diego Zoo, many additional condor chicks have been hatched and released bringing the total number of wild animals up to around 400. But raising a condor chick from an egg is no easy matter. The zookeepers use a “condor puppet glove” a glove that looks like a condor so that the young birds do not imprint on humans when they hatch and become dependent on them for food. The first condor chick hatched this season has been named “Wesa” and it is already eating up to 15 mice a day.
There is excitement in the scientific community over the latest results from the Mars Curiosity rover experiments. A sample of Martian rock drilled out by Curiosity from what might have been an ancient lake bed has revealed a type of clay that contains all of the necessary elements to support life. That finding, together with the conclusion that fresh water was once present, means that Mars is the first confirmed extraterrestrial body where life was once possible. The next question is did Mars in fact have at least microbial life? The answer to that may not be forthcoming until future Martian visits.
We all know it’s important to recycle, but Global Animal presents a list of six recycling animals. You’ll meet birds that recycle papers clips and string; a dung beetle that recycles, well, dung; and a hermit crab that recycles bottle caps.
One of the most famous migrating insects, the beautiful monarch butterfly, may be in serious trouble. The number of monarchs that were able to arrive in Mexico for their annual migration hit a 20-year low. A census conducted by Mexico’s National Commission of Natural Protected Areas this year counted only 2.94 forest acres occupied by the monarchs. In the past, as many as 50 acres of the forest were occupied. What is decimating the monarchs? One major factor is changes in United States farmland management. Milkweed, a monarch staple food source which was once ubiquitous among corn crops, is now being virtually eliminated by modern pesticides. The second factor is extreme weather, which includes record drought and heat. Experts warn that if the monarch population declines much further, it’s future may be unrecoverable.
The Waterberg copper butterfly was a native of South Africa but was confined to a single microhabitat located in the Waterberg Mountains. The butterfly was last seen in 1994 and since then its original habitat underwent major ecological changes. Scientists were concerned that the insect was gone forever until one sharpeyed researcher did a search for similar habitats in South Africa using Google Earth, a free online program that generates detailed 3D maps of most of the world. That’s when he spotted an “isolated plateau near the town of Bela Bela, about 50 kilometers from the Waterberg copper’s previously known habitat.” Sure enough, when researchers checked out the area they rediscovered the Waterberg copper butterfly.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
Mostly unseen by human observers, a global war is taking place beneath our feet. Invasive colonies of Argentine ants have spread to every continent except Antarctica. They have overwhelmed local ant colonies and are gaining territory at a spectacular rate. The Argentine ant is just one of over 12,000 ant species, but it forms massive interconnected colonies and uses savage battle tactics to kill off competing ant species. The good news is that the Argentine ant might have met its match. The bad news is that the new contender is another invasive species: the Asian needle ant. The Asian needle ant can deliver a venomous sting. That along with its ability to withstand colder climates and begin its Spring life cycle earlier than the Argentine ant has contributed to its relative success. North Carolina State University is using citizen science volunteers who collect and send in ant samples from their areas to determine if the Asian needle ant will be the next invasive ant threat.
Millions of years ago, baby plant eating dinosaurs had plenty to worry about. Not only were they gobbled up by meat eating dinosaurs such as T. Rex and velociraptors, but they were also a quick meal for ancient crocodiles, called crocodilians. Recently, the fossils of a heretofore unknown small plant eating dinosaur were recovered from Utah. A crocodilian tooth was found buried in one thigh bone along with other marks known to be consistent with crocodile-type attacks. One paleontologist noted that our modern notion of dinosaurs being the dominant species of their day could probably use some revision.
In the several years that scientists have been desperately trying to solve the riddle of bee colony collapse many theories have emerged. Most recently, a disease called idiopathic brood disease syndrome or “IBDS” has been postulated. North Carolina State University researchers believe that something goes awry in a bee colony when the worker bees incorrectly suspect that the queen is compromised. When that happens, the workers are genetically programmed to kill the queen by swarming her and raising her temperature to a lethal level—the same technique the workers employ to kill a hive invader. The researchers believe that understanding why a queen bee is rejected may be key to solving the riddle.
Imported and even rented honeybees are often used by farmers to pollinate their crops. In this article from Science News, Lucas Garibaldi of the National University of Rio Negro and Argentina’s CONICET research network argues that we should encourage native pollinators and not rely so heavily on the honeybee. Data shows that when native pollinating insects were encouraged in an area, on any continent, crop yields were higher with or without the help of the honeybee. However, we have lost many native pollinating insects and what species remain may be insufficient to reach optimal crop yields. For example, using 19th-century records from an area in Illinois reveals that over half of the native insects that pollinated in that era are now gone.
Fans of Downton Abbey might relate to the grandeur of the 18th-century Glenmoriston Estate, which is now known as Dundreggan, in Scotland. Located not far from Loch Ness, the former estate includes 10,000 acres and a sporting “Lodge” of 23 bedrooms. In recent times the property has fallen into neglect, but that has proved to be a boon for nature. In this “lost world,” researchers have found 3,000 plant species and many animal species that were thought disappeared. In short, the grounds are a treasure trove of Scotland’s biodiversity. Now owned by a volunteer group, Trees for Life, one half million trees are being planted to restore what was formerly a Caledonian forest.
Perhaps it’s a British thing, but the Zoological Society of London has introduced a computer program called “Cat Map.” It’s an application with which residents can input the “names, types, location, and even color of London’s feline residents.” The real purpose of Cat Map is to draw attention to endangered big cats. Two of the London’s Zoo’s tigers are listed on cat map, as well as the remaining 300 Sumatran tigers. It is hoped that it will eventually grow to list many of the world’s endangered cat species.
Camels are forever associated with Middle Eastern deserts, but archeological discoveries are shedding new light on their actual origins. Dr. Natalia Rybczynski of the Canadian Museum of Nature has uncovered 3.5 million-year-old fossil fragments of a camel ancestor in northern Canada. The animal was larger than modern camels, eleven feet high, and had a single large hump and a thick coat of fur. It was adapted to the cold temperatures of northern Canada and its hump was used to store fat to help it survive lean times. Ironically, these adaptations have been modified and passed down to modern camels who now inhabit hot desert climates.
By the late 1800’s, whalers had so depleted the population of Pacific gray whales that their extinction seemed inevitable. However, international conventions regulating whaling and the whale’s inclusion on the United States endangered species list added needed protection in the 1960’s and 70’s. Today, conservationists can claim a success. The eastern Pacific gray whale population is around 22,000 individuals—a sustainable and in fact growing population. Gray whales have also become a tourist attraction and thousands of tourists “whale watch” in Southern California’s Baja area.
In the bible, locusts, the eighth plague, were sent to attack the Ancient Egyptians. In a testament to their tenacity, locusts remain a scourge even today. A swarm of 30,000,000 insects has been ravaging crops in Egypt. A smaller contingent of about 1,000,000 has now spread into Israel, where it has triggered the Agriculture Ministry to send out pesticide spraying aircraft.
NPR reports on a recent scientific estimate that between 2002 and 2011 African forest elephants had their numbers reduced by around 62% due to ivory poaching. That shocking statistic reflects a slaughter that is going on every day in the Central African forests. The human actors who are contributing to this catastrophe include heavily armed poachers, the criminal gangs that finance them, and corrupt African officials and employees who overlook or participate in the illegal ivory trade. But what is really driving the demand for ivory and the poachers who shoot elephants to get it is the burgeoning Chinese middle class who clamor for more ivory. Elephants are highly intelligent, sentient animals and there is evidence that they are aware, on some level, of the genocide that is exterminating them.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.
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