Coral White Plague.
A disease that turns coral white from the base up is spreading in the Caribbean. Not too many years ago it was just an occasional occurrence, but now it is widespread and is having a negative impact upon the coral reefs of the Caribbean. New studies suggest that rather than being caused by a bacterial infection, the plague might be viral. Overfishing, which reduces the fish population and thereby increases the algae that grow on coral, is thought to play a role in the propagation of the white plague. Experts consider the disease a serious threat because it spreads quickly and can kill off entire fields of coral.
Forest, Heal Thyself.
After a forest has been cleared by logging, a change occurs when the forest begins to grow back. The trees that remain somehow increase their rate of grabbing nitrogen from the atmosphere and releasing it into the soil, which in turn speeds the recovery of the forest. When scientists compared forests that were in the second year of recovery with those that had been recovering for decades they found that the trees in the newly rebounding forests had nitrogen fixation rates that were up to “nine times faster” than that of the older trees.
Rhesus Monkeys Make a Home in Florida.
In the 1930’s, a misguided tour operator thought it would be a good idea to bring some rhesus monkeys to Florida as a prop for his tour boat operation. The monkeys escaped and now over a thousand are living in the wild in Florida. What concerns some experts is that the monkeys are known to be infected with a version of the herpes virus, which might be transmittable to humans. While cross species transmission is rare, it can be lethal when it occurs.
Behavior in Crickets Tied to their Parasites.
Normally, the female of a species is primarily responsible for the choice of a mate. However, researchers have noted that when female crickets are infested with a parasite they become far less choosy about with whom to mate. Rather than a purely chemical change caused by the parasites, some researchers have proposed that the parasites may make the females crickets stop producing eggs. This suddenly short window of reproductivity for the eggs that remain might be the impetus that causes them to mate quickly.
Our Martian Connection?
A well-respected organic chemist, Steven Benner, has suggested an unusual explanation for how life started on earth. As reported last week, it appears that early earth lacked some of the fundamental elements and compounds and dryness that seem necessary to produce the precursor of life, RNA. But analysis of martian meteorites suggest that Mars may have had oxygen as well as compounds called borates and molybdate, both of which could produce RNA in the presence of oxygen. But how did the Martian elements get to earth? Benner’s theory is that meteoric impacts on Mars could have kicked organic starting material off the surface and out of Mars’ orbit where it ultimately reached earth as Martian meteorites and in a sense “seeded” earth for life.
“The Ugly Animal Preservation Society.”
In Great Britain, some conversationalists are fed up with the human bias towards cute and furry animals. In order to increase public awareness of the many not so cuddly species that deserve human protection, they have turned to comedy. Various professional comedians and some scientists who try their hand at comedy have combined to champion some of the ugliest endangered species you have never heard of.
The DNA of the Big Cats.
In an effort to increase the genetic diversity of the world’s remaining large cats, a tiger’s entire genome has been sequenced. Its DNA will be compared to tigers, lions and leopards around the world to determine just how inbred the remaining populations of large cats have become. But the sequencing also has provided some interesting information about the evolution of the cats. For example, a tiger’s DNA is 95.6% similar to that of the domestic housecat. The housecat and the tiger last had a common ancestor around 10.8 million years ago. And certain genetic changes in the tiger’s DNA allowed it to become an exclusive meat eater and to have powerful fast-twitch muscles necessary for hunting down prey. In the case of the snow leopard, which lives at high altitudes in the Himalayan Mountains, genetic changes, similar to those discovered in the naked mole rat which lives underground, allow it to survive on low oxygen levels.
What can science possibly learn from termite poop? Actually, quite a lot. It turns out that termite excrement is used by termites to cultivate helpful bacteria that keep them disease-free. Just as the human digestive system cultivates bacteria internally to sustain health and fight off dangerous pathogens, the termite uses its excrement externally, as part of its construction of nests, for pretty much the same reasons. But the real payoff from studying termite excrement might be the discovery of new bacterial agents that can help wage what is becoming a losing war against antibiotic resistant germs that infect many hospitals.
Tiger Growls Help Farmers.
In India, wild elephants and farmers often have a contentious co-existence. Destruction of crops by elephants and deadly retaliation by farmers is a cause of concern to conservations who are trying to preserve the quickly diminishing wild elephant populations of the world. A new idea might come in the way of an audio recording. Since elephants fear tigers, recorded tiger growls, played by hidden speakers seem to do the trick and the elephants slowly back off from the farmer’s field when the recordings are played. Interestingly, a similar strategy is used in Africa where wild elephants are scared off by the recorded buzzing sounds from bee hives.
New York Times science writer Carl Zimmer discusses some new thinking about genetics that may affect medicine in a big way. Despite the commonly held belief that each individual’s DNA uniquely defines who they are, it turns out that many individuals carry around genes that belonged to other people. Sharing a uterus with a twin, giving birth to a child and even receiving a transplant donation are just some of the ways that some cells of our bodies are formed from DNA that is decidedly different from the rest of our cells. How this new realization will affect medicine and even impact the forensic sciences will probably be the focus of the next decade.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.