Cambrian prehistoric predator evolution, new research

This video says about itself:

26 March 2014

T[amisiocaris]. borealis, an ancient predator, probably used its spiny appendages to sweep through the water for prey and then bring it into its mouth, as these animations show. Credit: Martin Stein. Read more here.

From Wildlife Extra:

Large ocean predators evolved into gentle giants 520 million years ago

April 2014: Large marine creatures that roamed the Earth’s oceans more than 520 million years ago have been found to filter food from the water in a similar way to today’s blue whales and evolved into a gentle sea giant from a large marine predator that feasted on large prey, say scientists.

Newly discovered fossils from North Greenland showed that these ancient giant marine animals used bizarre facial appendages to trawl for nekton and plankton from the seas.

The North Greenland fossil, called Tamisiocaris, was a member of the iconic anomalocarids group of early marine animals which roamed the Cambrian and later Ordovician oceans. They swam using a set of flaps down either side of the body and probably captured large prey with specialised grasping appendages in the front of the mouth.

The team demonstrates that the Tamisiocaris had evolved into a suspension feeder by modifying its grasping appendages into a filtering apparatus that could be swept like a net through the water trapping small crustaceans and other organisms as tiny as half a millimetre in size.

The research, funded by the Agouron Institute, Carlsberg Foundation and Geocenter Denmark, was led by the University of Bristol and also included researchers at Durham University, the University of Bath and the University of Copenhagen.

As well as shedding light on the evolution of the Tamisiocaris, the researchers said their discovery also showed how productive the Cambrian period was and how vastly different species of anomalocarids evolved at that time. It also provides further clues into the ecosystems that existed hundreds of millions of years ago, they said.

Study lead author Dr Jakob Vinther, a lecturer in macroevolution at the University of Bristol, said: “The fact that large, free-swimming suspension feeders roamed the oceans tells us a lot about the ecosystem.

“Feeding on the smallest particles by filtering them out of the water while actively swimming around requires a lot of energy – and therefore lots of food.”

In order to fully understand how an anomalocarid could have fed, Dr Martin Stein from the University of Copenhagen, Denmark, created a 3D computer animation of the feeding appendage to explore the range of movements it could have made.

Dr Stein said: “Tamisiocaris would have been a sweep net feeder, collecting particles in the fine mesh formed when it curled its appendage up against its mouth.

“This is a rare instance when you can actually say something concrete about the feeding ecology of these types of ancient creatures with some confidence.”

The research about this was published here.

April 2014: An international team of researchers from the US, China and the UK have discovered the earliest known cardiovascular system in fossilised remains of an extinct marine shrimp that lived over 520 million years ago. The finding sheds new light on the evolution of the body in the animal kingdom and shows that even the earliest creatures had internal systems that strongly resemble those found in their modern descendants: here.