Winners of the 2012 Nikon Small World Photomicrography Competition. It must have been so hard to pick a First Place Winner; there are some truly beautiful and remarkable photos there! I loved the first place winner (go to the site to see it) but being a sucker for the color blue, I loved this extraordinary photo even more: it is a close-up of a section of the leg of a ladybug; it won 15thplace.
15TH PLACE, Andrea Genre, University of Turin, Italy. Technique: confocal.
And just in time for Halloween, check out these adorable bat embryos! Black mastiff bat (Molossus rufus) embryos:
HALLOWEEN IS HERE
Spooky photographs from spooky discoveries. National Geographic has this ghastly gallery of photographs from zoological or archaeological finds. I leave you here with this “screaming” shattered skull with perfect teeth. It belonged to a British colonist at Wolstenholme Towne, Virginia. The settler did not survive a 1622 attack by Powhatan Indians (or so historians think).
Go to the link for extra thrills, I could not resist posting here the bush baby, also known as galago’s grooming claw. Does anyone need a good scratch?
ENDLESS FORMS MOST BEAUTIFUL
The talking beluga whale. An article has just been published in the journal Current Biologist, describing the vocalizations of a captive beluga whale named NOC, who tried very hard to imitate human speech, and if you ask me, succeeded. Go to the link below to hear the vocalizations, they are, to say the least, spooky, because they do sound like human gibberish, perhaps like a child trying to make funny nonsensical words or sounds. The whale made the vocalizations for about 4 years, until he reached sexual maturity, then he stopped making the "human" vocalizations but remained very vocal, making whale sounds. NOC learned to do "human speech" on command, and scientists were able to study the way in which he managed to produce the sounds by inserting catheters into his vestibular sacs (above the nasal cavity). The way NOC mimicked human sounds was by varying his nasal tract pressure and using his phonic lips (vibrating structures above the nasal cavity), while at the same time he over-inflated the vestibular sacs. Hope found the video for us!
Critically endangered blue iguana is bouncing back. The beautiful blue iguana (Cyclura lewisi), which lives exclusively in Grand Cayman Island, has been moved from the “critically endangered” to the “endangered” list. A very successful conservation effort brought the population of blue iguanas from a couple dozen individuals to 400 animals in 2012. The blue iguana almost became extinct due to habitat loss, predation by dogs and cats, and getting run over by cars on previously non-existing roads. The conservation program involved breeding the iguanas in captivity, only releasing them in the wild at 2 years of age, when they were big enough not to be easy prey. These gorgeous reptiles live to be 60 years old and they grow to over 5 feet long.
Two new fern species named after Lady Gaga. Who says that scientists don’t have a sense of humor? An entire new genus of ferns, including 19 species, has just been officially named after Lady Gaga. An entire genus of ferns from Arizona, Texas, Mexico and Central and South America, has been named after pop star Lady Gaga. “We wanted to name this genus for Lady Gaga because of her fervent defense of equality and individual expression,” said Duke University biology professor Kathleen Pryer. “And as we started to consider it, the ferns themselves gave us more reasons why it was a good choice.” The scientists were inspired by Lady Gaga’s costume (in the photo), which looks exactly like the bisexual reproductive stage of the ferns. Most of the species in this genus are reclassifications of known species, but two are entirely new to science: Gaga germanotta from Costa Rica, (the species name is Lady Gaga’s actual last name), and Gaga monstraparva("monstraparva" means “little monsters” in Latin, which is what apparently Lady Gaga’s fans call themselves). Ra Ra Ra Ah Ah, Roma Ro Mo Ma, Ga Ga Ooh La La for science and for speaking up for equality!
Did cooking made us big-brained? A team of Brazilian scientists think they have the answer why other apes have no evolved big brains like we did: not enough calories in raw food to sustain brain growth. Our massive brains are energy hogs, they consume 20% of all calories when we are at rest. Karina Fonseca-Azevedo and Suzana Herculano-Houzel from the Federal University of Rio de Janeiro used data on brain, neuron numbers and body size from 17 species of primates, from marmosets to gorillas. They concluded that to afford a brain size like ours, a gorilla would have to have a maximum body size of only 43 kilograms (94 lbs, a truly mini-sized gorilla that would be!), and eat 8 hours a day (which gorillas actually do). Even worse, the brain of that hypothetical gorilla would only have half the neurons our brains have. In other words, in order to have a big brain weighing 2% of our total weight, like we do, an ape would have to sacrifice body size and number of neurons, neither very attractive trade-offs. The two scientists calculated that Australopithecus (“Lucy”), could have had ~40 billion neurons (we have ~86 billion neurons), and maintain them by eating an ape-like diet for 7 hours a day. But Homo erectus or even Neanderthals could not have had the big brains they had by eating raw foods like apes. They speculate that cooking foods, which make more calories available, is what allowed our ancestors to became both big brained and with a larger number of neurons. Other scientists disagree with that conclusion about cooked foods, and think that eating more meat and fat, even if raw, could have provided enough calories to develop big brains. The issue is, nobody knows how apes efficiently apes digest raw animal foods, and how many calories can be extracted from raw meat with an ape’s digestive system. It’s hard to study, because it would involve chimps, but it would be fascinating to know. After all, there is some evidence that Homo erectus was cooking 1.9 million years ago. I like this cooking=big brain hypothesis.
How humans almost became extinct 70,000 years ago. National Public Radio (which Mitt Romney wants to do away with!) has a great article on the Toba volcano explosion that occurred 70,000 and nearly caused our extinction. Genetics indicates that roughly 70,000 years ago we suffered a massive population bottleneck, in which the entire global population of humans was somewhere between 5,000 and 20,000 individuals. We sure have been busy making many little humans since then, given that we currently number in the billions and are a force to be contended with all over our planet. It's a fascinating episode in our prehistory. Think about this: we almost became extinct less than 100,000 years ago (the blink of an eye in evolutionary terms); we are all so closely related, every single one of us the progeny of tough survivors.
New Evidence That Grandmothers Were Crucial for Human Evolution. Women are unique among female primates in that they undergo menopause, while chimps and other apes do not; they continue to be fertile basically up until they die. They are not as long lived as we are either. Female chimps die in their forties. But would it be beneficial for females to stop being fertile when our life span still has a few more decades to go after menopause? In principle, it does not make evolutionary sense, because women who reproduce till later years would in theory leave more progeny and thus pass on more of her genes. But we humans are special because our babies and children are so dependent on us for so long. The “grandmother hypothesis,” proposed Kristen Hawkes in 1997, stated that menopause allowed women to better take care for their sons and daughters’ children, ultimately resulting in more surviving progeny. Further, she proposed that grandmothering contributed to the evolution of cooperation and social skills, ultimately resulting in bigger brains. In collaboration with mathematical biologist Peter Kim of the University of Sydney, Hawkes tested this hypothesis with computer simulations. The results were just published in the journal Proceedings of the Royal Society B. The answer is if we live as long as we do now, it’s because of grandmothers. The computer simulated a hypothetical ape with a life span of ~40 years (like a chimp) in which 1% of the population underwent menopause and had grandmothers caring for grandchildren. In the computer simulation, the ancestral females who survived for longer and became menopausal, helped cared for grandchildren, resulting in a survival advantage for them. In about 60,000 years, that hypothetical ape evolved the a longer lifespan, surviving into their 60s and 70s instead of dying by age ~40, with 43% of the adult female population becoming grandmothers. The evolutionary reason for menopause would then be that if older females were still fertile, they would continue bearing progeny and therefore not be able to contribute to the survival of her grandchildren, and once older mothers died, their children would likely die as well. From an evolutionary perspective, it makes sense for old females to contribute to her family’s overall survival rate instead of spending energy on producing more children that would be likely to die anyway.
Mitochondria-swap technology ready for the clinic? Did you that mitochondria, the cell organelles that provide the cell with energy, can be the cause of genetic diseases? They have their own DNA, and they mitochondrial defects can be fatal, as carnitine deficiency, which prevents the body from using fats for energy. Mitochondria are inherited only from the egg, so replacing defective maternal mitochondria could prevent these diseases from occurring. A few years ago, scientists have created eggs with “donor” mitochondria from rhesus monkeys, and they developed into healthy animals. The same team has now reported they can do the same trick with human embryos. What they did is removed the nucleus from a non-fertilized egg and replaced it with that of another non-fertilized egg, thus creating an egg from two mothers, “mitochondrial mom” and “nucleus mom” (“nucleus mom” would be the equivalent of what we know as simply “mom”, given that most of our DNA comes from the nucleus), and then fertilize the egg. For ethical reasons, they could let the embryos go until they were about 100 cells only, but up to that point, the human embryos with 3 parents were perfectly "healthy" and viable. The scientists claim the technique will be ready for use in the clinic in just 3 years, but other claim (in my opinion, rightly so) that we need more data from the monkeys, to show whether the animals bred using the technique are totally normal later in life and that they, in turn, can have healthy babies. If this technology was ever approved to help families with known mitochondrial DNA defects to bear healthy children, it would not be hard to implement in fertility clinics: all you need is a microscope and tiny lasers to drill into egg cell, stuff that fertility clinics already use for pre-implantation testing after in vitro fertilization.
Biology and ideology: The anatomy of politics. Nature just published an excellent review article on what is known about how our biology affects our ideology, in other words, how our political beliefs may not be entirely rational, but rather shaped by our responses to emotions such as disgust, fear, empathy, etc., and how these responses may be influenced in turn by hormones, and the way our brains respond to stimuli. This is a hot topic in neuroscience, psychology and philosophy at the moment: are liberals and conservatives destined by their biology to be such? I personally think that there is some truth to that, our personalities are influenced by biology and our ideology is heavily influenced by our personalities and the way our individual minds work. But obviously people change their minds and change ideologies frequently enough, that biology cannot be the whole picture. The article is thoroughly enjoyable, I recommend reading the entire piece.
Italian seismologists convicted of manslaughter for miscommunicatin.... Something remarkable and quite outrageous happened in an Italian court this past week: seven earthquake scientists were convicted of manslaughter for the deaths of people in the 2009 L’Aquila earthquake. Many in the media said they were convicted for failing to predict the earthquake, but that is not the case. The prosecutor and judge understand that earthquakes cannot be predicted. The manslaughter conviction came from a failure to communicate risks. The scientists were all part of an official commission assessing the risk of a major earthquake in light of increased tremors in the area. The scientists stated that the risks were heightened but that it was impossible to predict if and when an earthquake would occur. Apparently city officials then went on to reassure the public that minor shocks did not mean an increase in the risk of a major earthquake. According to the prosecutor, this led 29 victims who died when their houses collapsed during the earthquake, to stay in their homes instead of leaving the city. The prosecutor faulted the scientists for communicating the risks inadequately, which led local authorities to give an incorrect message to the public. The whole thing is crazy, because even if city officials had said that the risks were heightened, how can people just pick up their stuff and go? For how long would they have left? An earthquake is not like a hurricane, that you can track it. That earthquake may have never happened, or it may have happened way after the warnings. Certainly it seems insane that builders who skimmed on materials or broke building regulations, making houses that collapsed easily, are walking around free, when scientists risk up to 6 years in prison for not communicating to city officials in a “clear way.” It certainly makes scientists more reluctant than ever to participate in any sort of risk assessment commission. Hopefully the sentences would be overturned after the appeal.