Wednesday, August 24, 2005
Strange fossil defies grouping
A strange fossil creature from the early Cambrian Period is baffling scientists because it does not fit neatly into any existing animal groups.
The 525 million-year-old soft-bodied animal might have belonged to a now extinct mollusc-like phylum, scientists from America and China say.
Other researchers have suggested the creature could represent an early annelid or arthropod.
Details are published in Proceedings of the Royal Society B.
The 5-10cm-long (2-4 inch) creature, Vetustodermis planus, had a flattened body and horizontal fins which, researchers think, could have been used to support it as it moved along the sea floor. It also had well developed senses, including a pair of eyes on stalks.
The trouble is the animal did not possess a key set of features, or characters, which placed it clearly within any known group.
When it was first described in 1979, Vetustodermis was included in the annelid category. Later researchers argued against this classification, saying it was, in fact, either an arthropod or a mollusc.
The 525 million-year-old soft-bodied animal might have belonged to a now extinct mollusc-like phylum, scientists from America and China say.
Other researchers have suggested the creature could represent an early annelid or arthropod.
Details are published in Proceedings of the Royal Society B.
The 5-10cm-long (2-4 inch) creature, Vetustodermis planus, had a flattened body and horizontal fins which, researchers think, could have been used to support it as it moved along the sea floor. It also had well developed senses, including a pair of eyes on stalks.
The trouble is the animal did not possess a key set of features, or characters, which placed it clearly within any known group.
When it was first described in 1979, Vetustodermis was included in the annelid category. Later researchers argued against this classification, saying it was, in fact, either an arthropod or a mollusc.
