Smaller Domiciles Force Frog Monogamy
Animals aren’t well known for their monogamy. The name of the game is spreading the seed, and the more eggs you can fertilize, the better. The cost of being monogamous typically outweighs the benefits, and most non-mammalian offspring can fend for themselves straight out of the nest, so there’s often not a reason for mates to stay together after copulating. Dolphins, elephants and some types of birds are known to mate monogamously, some for life, but the “lesser” species tend to follow a more polygamous route. So, who would have thought that a mere frog would be willing to spurn its lothario ways and make a cozy home with the mistress?
Deep in the rainforests of South America dwells the Peruvian poison frog (also known as the mimic poison frog), and he is the epitome of a doting husband… as long as the dwelling demands his monogamy. Dr. Jason Brown and his colleagues from East Carolina University have found that the male mimic poison frog is forced into monogamy due to the small pools of water that the tadpoles are kept in.
After the tadpoles hatch in a communal puddle, the male takes each tadpole to its own dwelling inside a small pool of water captured within a plant. These pools of water are too small to offer any real sustenance, so the female frog must come along occasionally and lay unfertilized eggs for the tadpole to eat. The female is alerted to the tadpole’s hunger by the father, who keeps a close watch on his offspring. In fact, he must keep such a close eye that he is prevented from sneaking off and mating with any other available females.
The variable poison frog, a close relation to the mimic poison frog, however, engages in polyandry. Its eggs are laid in larger pools of water, usually five times larger than the pools of the mimic poison frog. The female lays the eggs and says sayonara, leaving the male to raise the brood.
When researchers upgraded tadpoles from diminutive puddle to palatable pool, the tadpoles flourished. It seems that the larger the area of water, the more nutrients available to the tadpoles – the female doesn’t need to lay protein-rich eggs to keep them growing, she is free to leave and the male is free to wander. However, in a smaller pool, both the male and female frogs are necessary for the tadpole’s survival.
Source: News BBC
Promiscuity Prevents Extinction
Speaking of promiscuity, new research showed that wandering eyes may prevent extinction. Males are usually blamed for engaging in promiscuity, but in the vastness of the natural world, females are typically the ones with multiples mates.
According to research conducted by the Universities of Exeter and Liverpool, promiscuity reduces the risk of populations becoming extinct due to them being reduced to all-female broods because of a chromosomal mutation. This chromosomal disorder causes all Y-chromosome sperm to be killed before fertilization, resulting in a sex-ratio distortion. Female offspring become carriers of the SR chromosome, which can be passed on to their sons and daughters. Eventually, because the males are not able to reproduce and create male offspring, the population will turn all-female: a paradise for Sappho, but a nightmare for genetic evolution.
To test the ramifications of polyandry as compared to monogamy, researchers divided the common house fly into two sets. One set housed females that could have as many mates as they could handle; in the other group, the females were restricted to a single mate.
Over 15 generations, five out of 12 monogamous populations became extinct because of a lack of males, due to the spread of the SR chromosome, which was less prevalent in the populations with multiple mates. Having multiple partners greatly reduced the spread of the SR chromosome – males that carry the chromosome produce half as much sperm as those without it. Females with multiple mates are far more likely to be fertilized by a male not carrying the SR chromosome, because their sperm outnumbers the amount coming from SR-carrying males.
Source: Science Daily
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Super Kamoikande Go!
Super-Kamiokande: it sounds like a Dragonball Z power move or the title of a futuristic anime set in space. In reality, it’s a gigantic neutrino detector, encasing 11,200 photomultiplier tubes set within 50,000 gallons of pure water. This “Super-K” detector is set to answer one of the most mind-boggling questions of our time: Why does matter exist?
According to super fancy physics laws that I couldn’t possibly explain, after the Big Bang, there should have been equal amounts of matter and anti-matter. Equal amounts of the duo would annihilate each other, leaving nothing behind but high-energy photons. Instead, there’s more matter than anti-matter in the universe, and we have no idea why.
The Tokai-to-Kamioka experiment, cleverly titled the “T2K,” will soon be conducting the most sensitive neutrino experiment ever to try to answer this question. Streams of neutrinos will be beamed from a particle accelerator located near Tokai and 300 miles to the opposite coast of Japan to the “Super K” detector at Kamioka. During their travel, the neutrinos will likely collide with atomic nuclei, creating a distinctive flash that scientists at the receiving detector will be on the lookout for.
Neutrinos come in three different types: electron, muon and tau neutrinos. Physicists know that neutrinos can change into one of these types spontaneously, and switch back and forth from one kind of another. They’re hoping that this oscillation holds the key to answering the question of why there is more matter than antimatter. During the experiment, physicists will be measuring how many neutrinos turn into electron neutrinos (anti-neutrinos). The collected data will later be used to compare neutrinos to anti-neutrinos, and finally, matter to antimatter.
“There must be a law of physics that is different for matter than antimatter,” claims David Wark of Imperial College, London. “We don’t know what it is, but neutrino oscillations are someplace where it might show up.”
Source: Popular Science
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Take Home Disease Kit Costs a Penny
Here’s a partial answer to our health care woes: a piece of paper that can fit into the palm of your hand and diagnose diseases for the cost of a single penny.
George Whitesides, a Harvard University chemist, has created a new “chip” technology using slices of treated paper and comic book ink. When a drop of blood is pressed to one side of the paper, it’s funneled into tree-like branches. Each layer of paper reacts to the blood and changes colors, reflecting the presence of diseases and the severity of it. This test will be able to detect malaria, AIDS, tuberculosis, hepatitis and other diseases.
Not only could this “lab in a chip” greatly reduce the increasing costs of simple tests, but patients in Africa or other third world countries would be able to take a picture of the results, send it to doctors worldwide, and receive diagnoses. Of course, they will still need to visit a clinic to receive proper treatment and medication, but this is certainly a step in the right direction.
“Today, many people don’t get the necessary diagnosis that will lead to access to the right treatment because diagnostic tests and lab tests are, most of the time, out of pocket,” explains Dr. Gaby Vercauteren, a coordinator at the World Health Organization. “People don’t have the money to buy that. Therefore, often, diseases are not diagnosed or only diagnosed far too late.” However, Vercauteren also warns that the paper may not fare so well in tropical climates: it may gather mold due to the humidity, rendering it ineffective.
Whitesides introduced his prototype “lab in a chip” at the TEDActive conference this year. Check it out, it’s rather inspiring.
Source: Popular Science
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Lauren Admire remembers when…well…never mind. She actually can’t remember when anything cost just a penny.
