Date of first walker pushed back 30 million years

A tiny trackway discovered in sedimentary rock has pushed back the date of the first organism capable of walking to 585 million years ago. This proof is 30 million years older than previously known evidence.It took two years to precisely date the trackway by radiometric dating of igneous rock that intruded into the sedimentary rock. The fossil was found in Uruguay.

The organism was about the size of a grain of rice. A trackway like this shows that it had front and back ends and was bilaterally symmetrical, with limbs that could move it forward. We could call it First Explorer.

See also Study resets date of earliest animal life by 30 million years.

Traces of evolution

I’m reading Animals without Backbones, Volume 2, and every so often I read something that reminds me of our long, long chain of common descent. It’s an old book, about 60 years old, but that means it’s simple and readable. Sure, every so often I mark something to look up in a newer book. But it’s great casual reading.

For example, roundworms, such as earthworms, have developed hemoglobin to help them carry oxygen around their bodies. It’s just floating in their blood: they haven’t developed blood cells. But it’s there. Six hundred million years separate us, but we have hemoglobin, too, slightly different but recognizably a related molecule doing the same job, with random changes in the non-functional parts. Isn’t knowledge wonderful?

You can read more about roundworms here. Or you can read about out last common ancestor (European Molecular Biology Laboratory (2010, February 1). Last ancestor humans shared with worms had sophisticated brain, microRNAs show. ScienceDaily. Retrieved January 21, 2012, from http://www.sciencedaily.com­ /releases/2010/02/100201101905.htm).

Early evolution of brachiopod eyes

It seems that brachiopods had simple eyes 600 million years ago. PZ Myers at Pharyngula explains how we know about them: common feature likely features of a common ancestor. Modern brachiopod larvae, even at a very early stage, show an earlier evolutionary stage: photosensitive pigment patches with no eye, no brain, and no nervous system. They drift towards a light source, which makes us think that

… light stimulation of the opsin is coupled to the activity of cilia used for motility in the outer epithelium of the embryo.

You can find out more at the Kewalo Marine Laboratory. Here’s a link to the article by  Passamaneck, Furchheim, Hejnol, Martindale, & Luter: Ciliary photoreceptors in the cerebral eyes of a protostome larva.

Child survives contact with box jellyfish

A ten-year-old girl in Queensland, Australia has survived stinging by a box jellyfish, an animal so deadly that for years it was known only by the marks on its victims’ bodies. The mysterious animal was called a sea wasp and was known for the severe, long-lasting, and sometimes fatal pain that it caused. Eventually divers and biologists discovered that it was a small, insignificant-looking, and almost cube-shaped jellyfish called a box jellyfish. One member of the box jellyfish family has been identified as the sea wasp, but all members are very venomous. It has long, fine, trailing tentacles almost like hair, but filled with stinging cells or nematocysts that discharge their stingers at a touch. All jellyfish have them but not all are dangerous to humans.

No one was worrying about jellyfish because the girl was swimming in the Calliope River, miles from the ocean. She was stung on the legs but managed to tell her brother before she collapsed.

Her 13-year old brother pulled her on to the shore and she told him that she could not see or breathe. Moments later she fell unconscious with the tentacles still wrapped around her limbs.

The venom of the box jellyfish is so overpoweringly painful that victims often go in shock and drown or die of heart failure before reaching shore.

Five months later, Rachel Shardlow is still being treated for the aftereffects.

U-Haul graphics

Nevada has an Area 51 stealth plane, Newfoundland has a giant squid, and Illinois has a Cambrian Explosion monster:

Text:

“llinois once lay near the equator on the supercontinent of Pangea and was home to unique creatures. How did the strip mining of Illinois’ coal deposits reveal the secret of the Tully Monster?”

The Tully Monster, discovered in 1958 in the Mazon Creek Lagerstaaten and named Tullimonstrum gregarium in 1966, is the state fossil of Illinois. Many have been found, but so far the Tully Monster is unique to Illinois. It dates back about 300 million years. We do not know what phylum it fits into. Its shape recalls the Anomalocaris, but that disappeared 100 million years earlier. Of course, with fossilization of soft-bodied organisms being so rare, perhaps it is a descendant of Anomalocaris!

Origami octopus by Joseph Wu

Octopus (hunting) take 5, originally uploaded by Joseph Wu Origami.

If anyone has a paper anniversary coming up, such as a year of blogging or a year since a creationist promised to “get back to you” about their debunked claim, one of Joseph Wu’s origami octopods might be the perfect gift—to themselves.

Darwin was right

Sea sponge

A new fossil discovery had proven that another of Darwin’s hypotheses about evolution was correct. During his lifetime, no animal fossils were known earlier than the Cambrian Explosion [of diversity], 540 million years ago. It occurred when animals developed hard body parts that could be fossilized, so some people call it an “induration.” It’s mostly in rare, fine limestones that you find the outlines, and sometimes the pigments, of soft body parts. Darwin, however, reasoned that evolution must have occurred for millions of years before the Cambrian Explosion for that diversity to develop. And he was right.

“Fossils push animal life back millions of years“

A novel technique used to date fossils buried in rock sediment in Oman shows that sponges, among the most primitive of animal organisms, flourished there more than 635 million years ago.

Stick insects!

Bishop Alan has a blog–and some stick insects or “walking sticks.” He wrote a series of posts all about his pet stick insects. He added his own close-up pictures of baby and adult stick insects, food plants, etc. His most recent article is called “Giant prickly virgin births.”