Asexual discrimination

This curious fernlike fossil is a rangeomorph, a member of a group believed (though no one is quite sure) to have been sessile animals. They lived on the seabed 565m years ago, during the Ediacaran period, which preceded the explosion of animal life during the Cambrian. The specimen shown is part of a study led by Nick Butterfield of Cambridge University, just published in Nature. Dr Butterfield and his colleagues wondered if they could work out how rangeomorphs reproduced. They looked at three places in Newfoundland where large fields of the fossil creatures are exposed, and mapped the precise location of individual specimens using the global positioning system. The pattern suggested rangeomorphs lived in groups that grew, by asexual reproduction, from a single individual (as a beech tree might put out suckers that grow into a copse). The founding individuals themselves, by contrast, grew from “propagules” that drifted through the ocean, as the larvae of many modern sea creatures do.

from The Economist: Science and technology http://ift.tt/1KMekmm