In the ever-ongoing effort to better understand the process of evolution, one researcher is focusing his efforts on a creature so small that its shells resemble mere grains of sand to the naked eye.
Called planktonic foraminifera, the fossils date back hundreds of millions of years and, in most cases, measure less than a millimeter in size.
"Because planktonic foraminifera have been around for many millions of years and rocks containing groups of their species can be dated precisely, we can use their fossils to see evidence of how species evolve over time," Thomas Ezard, an evolutionary ecologist at the University of Southampton and the study's author, said in a press release. "We can also see how differences between individual members of species develop and, in theory, how a new species comes into existence."
However, by calling attention to the small objects, Ezard is underscoring a debate regarding the best way in which to study speciation, or the phenomenon in which a new species is created.
At the heart of the debate is a disagreement over whether fossil records like the planktonic foraminifera are better equipped than the molecular study of evolution when analyzing speciation. While the latter uses evidence from today's species in order to look back in time, Ezard and those like him are more interested in using fossil records in conjunction with molecular models in order to recreate the past.
"The controversial hypothesis we test is that the processes leading to a new species coming into existence provoke a short, sharp burst of rapid genetic change," he said.
The reason this is controversial, he explains, is "because it is very difficult to detect these new species coming into existence accurately without the fossil data; it is more commonly determined from assumptions made from the study of species alive today using molecular evidence."
Through this approach, Ezard and his colleagues hope to increase the use of both types of data in the complex study of the evolution of life everywhere.