Here’s Elizabeth Turner, the paper author. And this week in Nature, there’s a paper that claims to have found a sponge from 890 million years ago. They also have far fewer cell types than other animals, so they may not be a bad place for an evolutionary start. They survive by filter feeding from water. Sponges – and, yes, they are animals, think about that next time you’re in the shower – don’t have complicated nervous, circulatory or digestive systems. One of the reasons that sponges, in particular, are such a focus of interest is that they’re often accepted to be the most basal of animals. There are also many theories for what the earliest animals may have looked like.
So, this is really just a family tree based on relatedness of DNA, and when you do this for elucidating the origin of animals, most molecular phylogenies suggest that the origin of animals was anywhere between approximately 650 and 850 million years. The other set of the problems – as if that wasn’t enough – is that the other way we have of trying to work out the origin of major changes in the evolution of life is to use what’s called molecular phylogeny. And hang on, didn’t Rachel say there were two major problems? But much earlier than that and things get much more murky. Scientists are pretty confident that some fossils from around 550 million years ago are animals. But going back into older rocks, it gets more and more uncertain. So, the Cambrian started at approximately 540 million years ago, so anything younger than that we can be pretty secure is an animal. We have fossils which we, being palaeontologists and geologists, can put our hands on our hearts and say, ‘This is definitely a fossil animal.’ And certainly, many, many fossils in the Cambrian are undoubtedly animals. First of all, the fossil record of animals is incredibly difficult to decipher.
This is Rachel Wood, a geologist with an interest in the evolution of life.Īnd this is for two reasons. Well, to be honest, we don’t understand when animals arose at all. When did the first animals evolve? It’s a more difficult question than you might think. Here’s reporter Nick Petrić Howe with more. We have another sponge story coming up now, albeit from much further in the past. I’m Benjamin Thompson.įirst up on the show, you might remember that last week we had a story about sponges. This week, possible fossil evidence of the oldest animal ever…Īnd eavesdropping on a glacier’s seismic whisper. Head here for the Nature Podcast RSS feed. Never miss an episode: Subscribe to the Nature Podcast on Apple Podcasts, Google Podcasts, Spotify or your favourite podcast app.
#OLDEST ANIMAL AGE FREE#
Subscribe to Nature Briefing, an unmissable daily round-up of science news, opinion and analysis free in your inbox every weekday. We hear about one researcher’s unorthodox attempt to listen in to the seismic-whisper at the foot of a Greenland glacier – a method that might reveal more about conditions under these enormous blocks of ice. Research Highlight: The guts of a ‘bog body’ reveal sacrificed man’s final meal 12:34 Eavesdropping on a glacier’s base Research Highlight: A caffeine buzz gives bees flower power Research Article: Turner 10:13 Research HighlightsĪ caffeine buzz appears to improve bees’ memory, and reconstructing an Iron Age man’s final meal. If confirmed, this would be more than 300-million-years older than the earliest uncontested animal fossils but not all palaeontologists are convinced.
This week in Nature, a researcher claims to have found a fossil sponge from 890-million-years-ago.
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