Old Weblog - June 2005
Palaeontologists think they have found a way to tell whether dinosaur fossils are from males or females. Writing in Science, a US team describe a specialised type of bone layer in fossils from a T. rex which is similar to one found in female birds. In birds, the special tissue is called medullary bone and is laid down in the limbs of females when they lay eggs. The bone tissue found in the dinosaur fossils most closely resembles the medullary bone of emus and ostriches.
See also: Bird bones offer insights to dinosaur sexing (New Scientist)
Scientists have extracted and decoded the DNA of a cave bear that died 40,000 years ago. They plan to unravel the DNA of other extinct species, including our closest ancient relatives, the Neanderthals.
If you are in ninth grade and live in Dover, Pennsylvania, you are learning things in your biology class that differ considerably from what your peers just a few miles away are learning. In particular, you are learning that Darwin’s theory of evolution provides just one possible explanation of life, and that another is provided by something called intelligent design. You are being taught this not because of a recent breakthrough in some scientist’s laboratory but because the Dover Area School District’s board mandates it. In October, 2004, the board decreed that "students will be made aware of gaps/problems in Darwin’s theory and of other theories of evolution including, but not limited to, intelligent design".
Scientists believe they have uncovered why people with a gene for a blood disorder are immune to malaria. It is known that people with a single gene for sickle cell anaemia, but not the full-blown condition, are somewhat resistant to the malaria parasite. Some say the distorted red blood cells caused by the gene are broken down quicker than normal by the body so malaria has no home in which to thrive. Now a Wellcome Trust team suggests the immune system also plays a big role.
It’s strange enough that beetles grow horns. But it’s especially strange that beetles grow so many kinds of horns.
The descendants of Charles Darwin are retracing his footsteps by surveying wild flowers in the meadows around his former home at Down House, in Kent. In June 1855, Darwin began a study of the local plants, which supported his theories on evolution and was mentioned in his book On the Origin of Species. Now, three generations of the Darwin family - aged from 21 months to 78 years - have begun a repeat survey. It should show how flowering plants have changed over the past 150 years.
Outrageously showy, notoriously fussy and surrounded by fawning admirers—it's no wonder orchids are sometimes referred to as the "supermodels of the plant world". It is difficult in a few, simple words to characterise this large family of flowers; even the experts will stop for a moment before launching into a long list of likely traits. But somehow you just know an orchid when you see one. "Sexual" and "flamboyant" are words that often come to mind. And if someone says something or someone is "orchidaceous", you instantly get the picture.
Darwin was fascinated by the sex lives of orchids. He studied them for years and went on to write On the Various Contrivances by which British and Foreign Orchids are Fertilised by Insects, and on the Good Effects of Intercrossing.
A ban on fishing sandeels in the North Sea is welcome but comes too late for this year's seabirds, says the Royal Society for the Protection of Birds… Many seabirds feed on the sandeel and its decline was blamed for the worst breeding season on record in 2004. But the RSPB says seabirds are breeding late again this year, and some are not even bothering to nest at all.
Israeli researchers say they have succeeded in growing a date palm from a 2,000-year-old seed. The seed was one of several found during an excavation of the ancient mountain fortress of Masada. Scientists working on the project believe it is the oldest seed ever germinated.
Darwin would have loved this story: he spent years experimenting on seeds to see if they managed to survive in all sorts of hostile conditions—sea water, birds' stomachs, etc.—all to establish how plants might colonise new environments.
A virus is placing Scotland's dwindling red squirrel population under threat, conservationists have warned. Squirrel pox is said to have been carried over the border by grey squirrels migrating north from Cumbria.
The extinction of New Zealand's giant, flightless moa birds may have been hastened by the long time they took to reach maturity, experts believe. UK and New Zealand scientists studied growth rings (similar to tree rings) in leg bones from the giant birds. They found that moa took about 10 years to reach full size and then several more to reach sexual maturity.
Few voyages have had more impact on science than Charles Darwin's visit to the Galapagos Islands in 1835… Charles Darwin's descendant Chris retraces part of the voyage for BBC Radio 4's It's My Story. He says the islands retain the sense of mystery and wonder that captivated his great, great grandfather.
The Linnean Society's entrance is tucked away in plain sight, just another stone portico and another dark oak door, across from the Royal Geological Society, and sharing a courtyard with the far larger Royal Academy of Arts. Inside, the headquarters is done in mustard and parchment white, with wood trim and brass, all very British and 19th Century.
Britain's biggest fish appears to be moving to Scottish waters—and experts say it may be down to global warming. Sightings of basking sharks are up 65% off the Scottish coast since 2001, but down 66% in south-west England, the Marine Conservation Society (MCS) said.
Bluffing, the oldest trick in the poker-player's book, comes in rather handy in the natural world, too. The peacock butterfly, a perfectly tasty snack for a bird, often cheats death with what is nothing more than a bluff. Suddenly exposing the prominent eyespots on the butterfly's wings is enough to startle a foraging bird and save the insect's life, says Adrian Vallin, a zoologist at Stockholm University, Sweden.
Nice little experiment, reminiscent of Kettlewell.
The population of rare Siberian tigers—once on the verge of extinction—appears to have stabilised in Russia's Far East, according to a new survey. Researchers found that numbers of the species in the region are about the same now as they were in 1996. Environmentalists say the tigers' survival is due to conservation projects and local education programmes.
For more on Siberian Tiger conservation efforts, see David Quammen's excellent book Monster of God.
Hardly bird brained, the diminutive black-capped chickadee sings one of the animal kingdom’s most intricate alarm calls, a new study reveals. These palm-sized puff balls increase the number of syllables in their battle cry depending on the deadliness of a sitting predator, says a team of US researchers.
On 1 July 1858, Charles Darwin’s and Alfred Russel Wallace’s ideas on evolution by natural selection were made public for the first time before the Linnean Society in London.
The World Summit on Evolution, held in the Galapagos Islands, revealed a science rich in history and tradition, data and theory, as well as controversy and debate
Evolution is poorly characterized by certain commonly used phrases. Properly communicating how evolution works requires careful attention to language and metaphor.