Two new creatures discovered from dawn of animal life

June 18, 2018 by Sarah Nightingale, University of California - Riverside

Earth's first complex animals were an eclectic bunch that lived in the shallow oceans between 580-540 million years ago.

The iconic Dickinsonia—large flat animals with a quilt-like appearance—were joined by tube-shaped organisms, frond-like creatures that looked more like plants, and several dozen other varieties already characterized by scientists.

Add to that list two new animals discovered by a UC Riverside-led team of researchers:

Obamus coronatus, a name that honors President Barack Obama's passion for science. This disc-shaped creature was between 0.5-2 cm across with raised spiral grooves on its surface. Obamus coronatus did not seem to move around, rather it was embedded to the ocean mat, a thick layer of organic matter that covered the early ocean floor.

Attenborites janeae, named after the English naturalist and broadcaster Sir David Attenborough for his science advocacy and support of paleontology. This tiny ovoid, less than a centimeter across, was adorned with internal grooves and ridges giving it a raisin-like appearance.

The discovery of Obamus coronatus was published online June 14 in the Australian Journal of Earth Sciences, or AJES, and the Attenborites janeae paper is forthcoming in the same journal. The studies were led by Mary Droser, a professor of paleontology in UCR's Department of Earth Sciences. Both papers will be included in print in a 2019 thematic AJES issue focusing on South Australia's Flinders Ranges region, where the discoveries were made.

Part of the Ediacara Biota, the soft-bodied animals are visible as fossils cast in fine-grained sandstone that have been preserved for hundreds of millions of years. These Precambrian lifeforms represent the dawn of animal life and are named after the Ediacara Hills in the Flinders Ranges, the first of several areas in the world where they have been found.

Read more at:

Shedding light on Earth's first animals

Complex and highly regulated development of Dickinsonia, one of the oldest fossil animals, broadens our understanding of early evolution

Date: May 17, 2017

Source: University of California - Riverside

More than 550 million years ago, the oceans were teeming with flat, soft-bodied creatures that fed on microbes and algae and could grow as big as bathmats. Today, researchers at the University of California, Riverside are studying their fossils to unlock the secrets of early life.

In their latest study, published today in the journal PLOS ONE, Scott Evans, a graduate student in the Department of Earth Sciences, and Mary Droser, a professor of paleontology, both in UCR's College of Natural and Agricultural Sciences, show that the Ediacaran-era fossil animal Dickinsonia developed in a complex, highly regulated way using a similar genetic toolkit to today's animals. The study helps place Dickinsonia in the early evolution of animal life, and showcases how the large, mobile sea creature grew and developed.

Dickinsonia was a flat, oval-shaped creature that ranged in size from less than an inch to several feet, and is characterized by a series of raised bands -- known as modules -- on its surface. These animals are of interest to paleontologists because they are the first to become large and complex, to move around, and form communities, yet little is known about them. For years, scientists have been debating the taxonomic status of Dickinsonia -- placing it with fungi, marine worms and jellyfish, to name a few. It is now generally accepted that Dickinsonia was an animal, now extinct.

Read more