Toxodon. Illustration by Peter Schouten from the forthcoming book “Biggest, Fiercest, Strangest” W. Norton Publishers (in production)
“Toxodon is perhaps one of the strangest animals ever discovered,” wrote Charles Darwin, a man who was no stranger to strangeness.
He first encountered the creature in Uruguay on November 26th, 1834.
“Having heard of some giant’s bones at a neighbouring farm-house…, I rode there accompanied by my host, and purchased for the value of eighteen pence the head of the Toxodon,” he later wrote.
The beast’s skeleton, once fully assembled, was a baffling mish-mash of traits.
It was huge like a rhino, but it had the chiselling incisors of a rodent—its name means “arched tooth”—and the high-placed eyes and nostrils of a manatee or some other aquatic mammal.
“How wonderfully are the different orders, at present time so well separated, blended together in different points of the structure of the toxodon!” Darwin wrote.
Those conflicting traits have continued to confuse scientists. Hundreds of large hoofed mammals have since been found in South America, and they fall into some 280 genera.
Scientists still argue about when these mysterious beasts first evolved, whether they belong to one single group or several that evolved separately, and, mainly, which other mammals they were related too.
“That’s been difficult to address because they have features that they share with a lot of different groups from across the mammalian tree,” says Ian Barnes from the Natural History Museum in London. “To some degree, people have circled around the same set of evidence for 180 years.”
Now, Barnes’ team, including student Frido Welker from the Max Planck Institute for Evolutionary Anthropology and Ross MacPhee form the American Museum of Natural History, have found a way to break out of the circle.
They recovered a hardy protein called collagen from the fossil bones of Toxodon and Macrauchenia, another South American oddity that resembled a humpless camel. By comparing these molecules to those of modern mammals, the team concluded
“Toxodon looks a bit like a hippo and we now know that the features they share with hippos are probably due to convergence,” says Barnes. “Macrauchenia looks a bit like a camel, but we can now see that it’s not particularly well related to camels.. This has been a longstanding mystery and we have an answer, and that’s satisfying.”
The discovery has bigger implications, though. Many scientists, Barnes included, have recovered DNA from very old fossils. They have sequenced the full genomes of mammoths and Neanderthals, worked out the evolutionary relationships of giant birds, and even discovered entirely new groups of early humans.
But ancient DNA has its limits.
To fish it out of fossils, you need molecular bait, and to design that bait, it really helps to know what kind of animal you’re looking for and what they’re related to. If you don’t, and your only clue is “er, some kind of mammal”, then recovering ancient DNA is hard.
It becomes harder if the fossils are also very old, since DNA has a half-life of around 521 years.
And it becomes absurdly hard if the bones come from warm climates, like most of South America, where DNA degrades even faster than usual.
by Annetta Black
The glass-domed conservatory at Huntington Gardens is home to many exotic plants, but tucked away in one of the wings is a special boggy environment dedicated to the most delightful plants of them all: the meat eaters.
On display within the massive 16,000 square-foot Rose Hills Foundation Conservatory are numerous species of unusual carnivorous plants, including American pitcher plants, sundews, Venus flytraps, and butterworts.
One example is the Sarracenia trumpet pitcher, native to the eastern United States, it flowers in the spring with a pretty little blossom and a distinctive smell, not unlike cat urine.
The pitchers are actually the leaves of the plant, and form slippery funnels that attract and trap curious insects.
Larger pitcher plants can trap and digest a full grown rat.
In comparison, the Drosera, or sundew, relies on hundreds of tiny sticky drops along their leaves to trap and digest insects.
There are more than 194 known species of sundews, making it the largest genera of carnivorous plant.
The humble looking Pinguicula, or Butterwort, with its pretty and unassuming purple blooms, uses a similar technique, trapping small insects on its sticky leaves.
The sabre-toothed cat or tiger is one of the most well-known prehistoric animals along with giants such as the woolly mammoth.
Sabre-toothed tigers roamed the mid-western United States and parts of both North and South America and were named for the enormous canines which skeletons show, protruded quite far out of their mouths.
It became extinct during the latter stages of the ice age. Despite the name, the sabre-toothed tiger was not actually related to the modern tigers that are found throughout the jungles of Asia.
It is thought that the sabre-toothed tiger would have roamed across the grassland plains and open woodlands throughout both North and South America where individuals would of varied slightly depending on the area which they inhabited.
The sabre-toothed tiger was named for the canines that could grow to more than 7 inches in length and were capable of fatally wounding their prey with one bite.
Sadly, the colour of the sabre-tooth tiger is unknown but it is thought that is would of been of a similar colouration to the modern day lion found in Africa (and which it is not closely related to).
The sabre-toothed tiger also had a powerful, muscular body which meant that it could quickly catch and pounce on it’s prey before using it’s knife-like teeth to cause to the fatal blow.
The sabre-toothed tiger was a carnivorous animal and would of been the most dominant predator within its environment.
Large herbivorous animals such as deer and bison would of been the most common prey of the sabre-toothed tiger along with occasional giant such as a small woolly mammoth should their ranges cross, although their exact diet is unknown.
The sabre-toothed cat would of been the most ferocious and therefore the apex predator within it’s environment so had no natural predators on the American plains.
Humans are thought to be the most likely cause for the demise of this enormous cat and more than 2,000 sabre-toothed tiger skeletons have been found emerged in the famous tar pits close to Los Angeles.
Photo: If you are stranded outside in an electrical storm do not shelter under tall objects such as trees or poles. (Rohan Coghlan: User submitted)
by Samantha Turnbull
It is storm season in Australia and, while being struck by lightning is considered a rare occurrence, there are several steps people can take to keep safe.
ABC science expert Dr Karl Kruszelnicki said there were roughly 100 lightning strikes every second around the world resulting in about 100 deaths per year.
He said the SAFEST PLACE WAS INDOORS during an electrical storm.
If you are indoors, the Bureau of Meteorology suggests UNPLUGGING appliances before the storm hits.
Dr Kruszelnicki said it was particularly important to STAY AWAY FROM TELEPHONES during a storm.
“If you have a landline phone connected by a wire to the exchange, lightning can hit anywhere along that line depending on how the wire travels (underground or overground),” Dr Kruszelnicki said.
“Telstra does warn there are cases where people have been harmed using a corded phone.
“You should SWITCH OFF all your electrical appliances, even switch them off at the circuit board.
“The Bureau of Meterology also advises anyone indoors to CLOSE all of their windows and doors and to stay away from openings including fire places.
Dr Kruszelnicki said the safest place to be was in the MIDDLE of the building. “Sit or huddle in the middle of the room and enjoy the show,” he said.
The Bureau and Dr Kruszelnicki also advised people NOT TO take a bath because water and metal are electrical conductors.
Please read the full article via How to protect yourself from lightning strikes – ABC News (Australian Broadcasting Corporation)
Image: Richard Solis
How did it happen? How’d the zebra get its stripes?
Rudyard Kipling wrote,
“a gray, horsey-looking beast went into “a great forest ‘sclusively full of trees and bushes and stripy, speckly, patchy-batchy shadows,” stayed there awhile, and after a “long time”… got stripey”.