Rangeomorph

The Rangeomorphs are a form taxon of frondose Ediacaran fossils that are united by a similarity to Rangea. Some workers, e.g. Pflug and Narbonne, suggest that a natural taxon Rangeomorpha may include all similar-looking fossils.

Rangeomorphs are a key part of the Ediacaran biota which survived about 30 million years, forming 80% of the fossils found from the Ediacaran period, until the base of the Cambrian Ma|542.

In 2004, extremely well-preserved fossils discovered in Newfoundland, Canada revealed some details of rangeomorph structure. They consist of branching "frond" elements each a few centimetres long, each of which is itself composed of many smaller branching tubes held up by a semi-rigid organic skeleton. This self-similar fractal-like structure could have been formed using fairly simple developmental patterns.

Rangeomorphs dwelt mainly in the deep ocean, were unable to move, and had no reproductive organs, perhaps reproducing asexually by dropping off new fronds. Rangeomorph communities are similar in structure to those of modern, suspension-feeding animals, but it is difficult to relate their morphology to any modern animals. They may represent an extinct stem group near the base of animals and fungi.

References

*cite journal |author=Narbonne GM |title=Modular construction of early Ediacaran complex life forms |journal=Science |volume=305 |issue=5687 |pages=1141–4 |year=2004 |pmid=15256615 |doi=10.1126/science.1099727

External links

* [http://www.newscientist.com/news/news.jsp?id=ns99996162 Article in New Scientist]