Fossil plankton from half a billion years earlier. These small algae step much less than a millimetre in size. They developed their colonial structure to prevent being consumed by early animals. Credit: THP Harvey
Microfossils going back half a billion years have actually been found by a researcher from the University of Leicester.
A researcher from the University of Leicester has actually found a brand-new kind of fossil that exposes life in the oceans half a billion years earlier.
The small organisms, detailed in a brand-new research study in the journal Proceedings of the Royal Society B, look like modern-day algae and may likewise offer researchers an insight into the environment modifications that impacted our oceans.
The fossils are tiny and appear like spiny balls linked together. The research study’s author Dr Tom Harvey, from the University of Leicester School of Geography, Geology and the Environment, stated: “When I first saw them, I had no idea what they were. I wondered if they could be animal eggs, or some new type of organism. There’s nothing quite like them, living or extinct.”
Dr Tom Harvey from the University of Leicester School of Geography, Geology and theEnvironment Credit: THP Harvey
But as additional specimens emerged, Dr Harvey determined resemblances with contemporary green algae that live drifting in the plankton of ponds and lakes. He describes: “The fossils have the same sort of colonial structure as the modern algae, with cells linking together, explaining their neat, geometric arrangements. Surprisingly, though, the fossil examples lived in the sea, giving a rare glimpse of the early marine plankton.”
A Link to the Cambrian Explosion
The significance of the fossils depends on their enormous age. They lived around the time when animals were very first developing, throughout the Cambrian ‘explosion’ of life– and this is most likely no coincidence. In today’s world, phytoplankton supplies the essential food source for nearly all life in the oceans. However, the contemporary groups of phytoplankton developed fairly just recently, and we do not understand which groups lived in the Cambrian oceans.
Dr Harvey describes: “When we take a look at contemporary plankton, we see that algae establish nests when animals are attempting to consume them. It’s a defense reaction. So, the presence of colonial algae in the Cambrian Period recommends that early animals were developing to feed in the plankton, beginning a predator-prey relationship that has actually continued since.
“Considering that the plankton underpins life in the oceans, and fossil plankton helps us build ancient climate models, these small fossils have a big role in telling the history of life on Earth.”
The brand-new discovery will trigger a re-think on other early microfossils. For years, researchers have actually believed that the spiny balls discovered separately were the inactive cysts of single-celled life.
For Dr Harvey, the brand-new fossils seriously challenge this view: “I wonder if we’ve been getting it all wrong, and in fact lots of these microfossils were living as colonies in the plankton. It’s easy to accidentally break up the fossils as we extract them from the rocks, so we all need to get back to the collections, back to our labs, and find out how common they really were.”
Reference: “Colonial green algae in the Cambrian plankton” by Thomas H. P. Harvey, 24 October 2023, Proceedings of the Royal Society B
DOI: 10.1098/ rspb.20231882
