Researchers have discovered that the Streptococcus bacterium acquired its "flesh eating" toxic shock power after an infection of its own from a bacteriophage, a form of virus that attacks bacteria, about 30 years ago. The bacteriophage inserted a gene into a strain of the strep bacteria that allows it to take the human plasminogen protein and convert it into the protease enzyme. This enzyme destroys the human tissue, enabling the rapid invasion of the body that characterises the vicious nature of this strain of strep.

The mutation also produces an enzyme which allows the bacterium to escape capture and death by the host body's white blood cells, or  neutrophils. This selects the mutated bacteria over their less virulent cousins without the gene. It's a gruesome example of evolution in action.

Reuters is reporting that the Awashima Marine Park in Shizuoka, Japan, captured a rare frilled shark. These primitive sharks are considered living fossils, looking more like eels than the more familiar shark types and may be found over a kilometre deep. While frequently caught in bottom dredging nets the frilled shark has rarely been seen alive. Caught in a poor state, the Awashima shark died shortly after capture.

The nice thing about the Web is that you come across all sorts of weird things, like this photo of blind Golden-line Barbell fish and can then research more information about them. These fish look like their eyeballs have been torn from their bodies, leaving just a gap. Click on the little red forward and backward arrows near the bottom of the latter link's page and you will find information on other related blind fish and their underground habitats. Fascinating.

Imagine that the ice planet Hoth from Star Wars: The Empire Strikes Back was real. How could life evolve, let alone survive, on a planet entirely covered with snow and ice? Was it always that way, or did some great catastrophe strike the planet and cause it to freeze?

I had a lot of fun writing up this report, researching the science behind areas as diverse as ice worms to goats to cometary dust falling on oceans. Could such a movie world as Hoth really exist, along with its ice lizards and ferocious predators? The surprise comes from what the quest for an answer to this question tells us about our own planet.

hoth.pdf (500 KB)
hoth_small.pdf (229KB) - low resolution images

A paper by Kaminski et al. in the June 11 issue of Science (also the Sydney Morning Herald) is reporting on evidence that dogs, like children, are able to infer the meanings of new words after a single exposure in a process known as "fast mapping". This knowledge can be retained for at least a month after the first introduction of the new word. Paul Bloom cautions the further testing may be required.

References

Bloom, P. 2004 Science, 304, 1605
Kaminski, J., Call, J. and Fischer, J. 2004 Science, 304, 1682