kisma Johnson's blog: "Fish Lives in log Breathes Air"

The immense fossilised claw of a 2.5m-long (8ft) sea scorpion has been described by European researchers. The 390-million-year-old specimen was found in a German quarry, the journal Biology Letters reports. The creature, which has been named Jaekelopterus rhenaniae, would have paddled in a river or swamp. The size of the beast suggests that spiders, insects, crabs and similar creatures were much larger in the past than previously thought, the team says. The claw itself measures 46cm - indicating its owner would have been longer even than the average-sized human. Overall, it exceeds the record for any other sea scorpion (eurypterid) find by nearly 50cm. The eurypterids are believed to be the extinct aquatic ancestors of modern land scorpions and possibly all arachnids (the class of animals that also includes spiders). "The biggest scorpion today is nearly 30cm so that shows you how big this creature was," said Dr Simon Braddy from the University of Bristol, UK. It was one of Dr Braddy's co-authors, Markus Poschmann, who made the discovery in the quarry near Prum in south-west Germany. "I was loosening pieces of rock with a hammer and chisel when I suddenly realised there was a dark patch of organic matter on a freshly removed slab," he recalled. "After some cleaning I could identify this as a small part of a large claw. Although I did not know if it was more complete or not, I decided to try and get it out. "The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilise it." Super-sized meals: The species existed during a period in Earth history when oxygen levels in the atmosphere were much higher than today. The fossil was locked in a siltstone from the Carboniferous Period And it was those elevated levels, some palaeo-scientists believe, that may have helped drive the super-sized bodies of many of the invertebrates that existed at that time - monster millipedes, *spam filter*roaches, and jumbo dragonflies.

A tiny western Atlantic fish does something never before seen: It makes like a bird, living in mangrove wood for months at a time. A team of U.S. and English scientists accidentally discovered the unique behavior, which they call "logpacking," during recent excursions to Belize and Florida. They were studying how the mangrove rivulus—an animal already infamous for its bizarre sexual behavior—survived the frequent dry spells that strike its swampy forest habitat. "One of us kicked at a log, which broke apart and out came the fish!" said team leader Scott Taylor of Brevard County, Florida's Environmentally Endangered Lands Program. Log-Dwelling Fish The mangrove rivulus, also known as the mangrove killifish, is native to the Americas and is about two inches (five centimeters) long. The fish has long been studied for its many unique features. It's the only vertebrate known to naturally self-fertilize, for example. In some populations, it can become a hermaphrodite, developing both male and female parts simultaneously, to produce clones of itself. (Related: "Sexual Orientation Is Genetic in Worms, Study Says" [October 25, 2007].) The animal can also live out of water for up to 66 days, Taylor said, and is one of very few fish species that spend their entire lives in mangrove swamps. Most fish move in and out of the areas as water sources dwindle. Taylor and his team had previously found that when small pools of water dried up, the rivulus settled into crab burrows. But even those disappear during extreme dry spells. "Sometimes the pools have very heavy [rivulus] populations, and they have to go somewhere when they dry," he said. "We had seen them under logs and in piles of damp leaves, inside coconuts, even in beer cans—for real."