Sunday 28 November 2010

When algae forgot to evolve – for a billion years



Somewhat younger algae. Image courtesy of Eric Guinther, Wikipedia.



Joel Kontinen


Researchers assume they have found new living fossils. The algae living at a depth of over 200 metres (650 feet) in the waters of New Zealand belong to the genera Palmophyllum and Verdigellas.

Recently, professor Frederick Zechman of California State University at Fresno and colleagues published a study on the genetic makeup of these algae in the Journal of Phycology. The researchers concluded on the basis of the algae’s DNA that they are closely related to algae they assume are a billion years old.

Although there are no fossils of so old algae, professor Zechman suggests that they are living fossils.

Evolution is often defined as change over time but it seems to have forgotten to change many species. For instance, the Coelacanth (Latimeria chalumnae), squids, octopuses, tuataras, horseshoe crabs and dragonflies have resisted Darwinian change for aeons.


Sources:

Deep-sea algae may be 'living fossils'. Physorg. com (19 November).

Walker, Matt. 2010. Ancient seaweed is living fossil. BBC News (18 November).