Painted Hula, Frog-Frog-A-Hula

A frog species native to Israel’s north which was declared extinct has been rediscovered and dubbed a “living fossil” — not only of its own species but of an entire genetic group, Jerusalem’s Hebrew University have announced.

Discovered in the Hula Valley in the 1940s, the Hula painted frog was thought to have disappeared following the drying up of the Hula Lake at the end of the 1950s, and was declared extinct by the International Union for Conservation of Nature in 1996.

The frog — individuals of which were found in the Hula swamp area two years ago — turned out “to be a unique ‘living fossil,’ without close relatives among other living frogs,” the university said in a statement.

© Sarig Gafny

A team of Israeli, German and French researchers authored a report in the scientific journal Nature Communications which details the results of a a genetic study of the amphibian, finding that the rediscovered Hula is actually the only living species of its kind.

“The Hula frog differs strongly from its other living relatives, the painted frogs from northern and western Africa. Instead, the Hula frog is related to a genus of fossil frogs, Latonia, which were found over much of Europe dating back to prehistoric periods and has been considered extinct for about a million years,” Hebrew University said.

The team — led by Hebrew University’s Rebecca Biton, Tel Aviv University’s Professor Rebecca Biton, Prof. Sarig Gafny of the Ruppin Academic Center and Dr. Vlad Brumfeld of the Weizmann Institute of Science – conducted “genetic analyses of rediscovered individuals” as well as “morphologic analyses of extant and fossil bones,” according to the statement.

“The results imply that the Hula painted frog is not merely another rare species of frog, but is actually the sole representative of an ancient clade of frogs (a group with a single common ancestor),” the university said.

Source: Times of Israel


Pesty Pests!

A strain of cockroaches in Europe has evolved to outsmart the sugar traps used to eradicate them.

American scientists found that the mutant cockroaches had a “reorganised” sense of taste, making them perceive the glucose used to coat poisoned bait not as sweet but rather as bitter. A North Carolina State University team tested the theory by giving cockroaches a choice of jam or peanut butter. They then analysed the insects’ taste receptors, similar to our taste buds.

Researchers from the same team first noticed 20 years ago that some pest controllers were failing to eradicate cockroaches from properties because the insects were simply refusing to eat the bait. Dr Coby Schal explained in the journal Science that this new study had revealed the “neural mechanism” behind this refusal.

In the first part of the experiment, the researchers offered the hungry cockroaches a choice of two foods – peanut butter or glucose-rich jam. “The jelly contains lots of glucose and the peanut butter has a much smaller amount,” explained Dr. Schal. “You can see the mutant cockroaches taste the jelly and jump back – they’re repulsed and they swarm over the peanut butter.”

~ original article & video of eww! cockroaches! here ~

In the second part of the experiment, the team was able to find out exactly why the cockroaches were so repulsed. The scientists immobilised the cockroaches and used tiny electrodes to record the activity of taste receptors – cells that respond to flavour that are “housed” in microscopic hairs on the insects’ mouthparts.

“The cells that normally respond to bitter compounds were responding to glucose in these [mutant] cockroaches so they’re perceiving glucose to be a bitter compound,” Dr. Schal said. “The sweet-responding cell does also fire, but the bitter compound actually inhibits it – so the end result is that bitterness overrides sweetness.”

Highly magnified footage of these experiments clearly shows a glucose-averse cockroach reacting to a dose of the sugar. “It behaves like a baby that rejects spinach,” explained Dr Schal. “It shakes its head and refuses to imbibe that liquid, at the end, you can see the [glucose] on the side of the head of the cockroach that has refused it.”

“Peanut butter & jelly” – a meal so good only cockroaches enjoy / reject it!

Dr Elli Leadbeater from the Institute of Zoology in London said the work was exciting. “Usually, when natural selection changes taste abilities, it simply makes animals more or less sensitive to certain taste types. For example, bees that specialise on collecting nectar are less sensitive to sugar than other bees, which means that they only collect concentrated nectar. Evolution has made sugar taste less sweet to them, but they still like it. In the cockroach case, sugar actually tastes bitter – an effective way for natural selection to quickly produce cockroaches that won’t accept the sugar baits that hide poison.”

Dr Schal said this was another chapter in the evolutionary arms race between humans and cockroaches. “We keep throwing insecticides at them and they keep evolving mechanisms to avoid them,” he said. “I have always had incredible respect for cockroaches,” he added. “They depend on us, but they also take advantage of us.”

Respect? Respect, sure! On the bottom of my boot…! Bleurgh, horrible things!

Madagascan Garment

A model wears a cape made from the silk produced by more than a million Madagascar Golden Orb spiders. The piece took eight years to create and uses fabric not woven in more than a century. The garment is on display at the Victoria and Albert Museum in London until 5 June.


Source: The Guadian
Photograph: David Levene

I feel a little disquiet over this, even though I’m no fan of ight-legged, air-breathing Arthropods, and even though probably none were killed in the making of the garment. Strange.