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Thursday 29 May 2008 (Updated on Friday 30 May 08 at 8pm AEST)

RAPID ROUNDUP: World’s oldest mother – live birth in the Devonian: Nature - experts respond

A team of Australian scientists have uncovered the world’s oldest vertebrate mother in a newly unearthed species of fossil fish. Published in Nature, the fossil shows a single embryo connected by an umbilical cord and is the oldest evidence of an animal giving birth to live young.

Dating back around 380 million years, the fossil is from an extinct class of armoured shark-like fishes known as ‘placoderms’. It was discovered in the Gogo formation, near Fitzroy Crossing in Western Australia which was part of an ancient barrier reef teeming with fish during the Devonian period 355-408 million years ago.

The new species has been named Materpiscis attenboroughi, after Sir David Attenborough, whose 1979 series Life on Earth first drew world attention to the Gogo fish sites.

Hear Sir David Attenborough's reaction to the news by clicking here (mp3 - 3 min). Sir David joined a live video conference briefing between London and Australia on the fossil fish. Read a transcript of Sir David's comments below.

Click here to see an animation of the fish giving birth. (Animation courtesy of Museum Victoria)

Follow the presentation given by the Nature co-authors on Wednesday 28 May in Adelaide which was screened live in London via a video conference link to coincide with the re-opening of the Royal Institution of Great Britain by Her Majesty Queen Elizabeth II. (NB: Several embedded animations are not currently visible in this version of the presentation. We hope to rectify this asap). Presenters were co-authors of the Nature paper: Professor John Long Dr Kate Trinajstic Associate Professor Tim Senden

The AusSMC has rounded up Australian experts to comment on this research. Feel free to use the comments below in your stories. If you would like to speak to an expert, or need a copy of the paper and media release, please don’t hesitate to contact us on (08) 8207 7415 or by email.

* An unveiling of the fossilised remains was also held at Melbourne Museum on Thursday 29 May at 12pm with Dr John Long, world-renowned palaeontologist and Head, Sciences, Museum Victoria. For further information on this unveiling please contact: Jessica Bendell on 03 8341 7726, 0439 341 007 or jbendell@museum.vic.gov.au

Professor John Long is Head of Sciences at Museum Victoria. John is a co-author of the Nature paper.

"I think this is one of the most extraordinary fossil finds of all time, as it is the first time in history we have a maternal feeding structure preserved in any fossil.

When I first saw the embryo inside the mother fish my jaw dropped, I was silent, stunned like a mullet. I realised that in my hands was the oldest known vertebrate embryo.

It dawned on me after studying the specimen that this was the earliest evidence of vertebrates having sex by copulation - not just spawning in water, but sex that was fun!

The find was one of several major discoveries we made on the 2005 Gogo Expedition, one of the others was the Gogonasus specimen which featured in nature in late 2006. We're going back there this year and hope to continue with our strike rate and find something else that will shed light on the early evolution of the first vertebrates. It's one of the main ways we make breakthroughs in palaeontology, to get out in the field and just keep looking."

Dr Kate Trinajstic is a Research Associate at the University of Western Australia. Kate is a co-author of the Nature paper.

“This amazing discovery was made possible by the rare fossilisation of soft tissue, allowing us to see that the embryo was inside its mother and connected by an umbilical cord. This is also the first evidence of sex in vertebrates with jaws. What this tells us is that unlike most other fish that lay eggs in the water, Masterpiscis eggs were fertilised internally, the mother provided nourishment to the embryo and gave birth to live young, much like mammals do today.“

Associate Professor Tim Senden is an ARC Research Fellow at the Australian National University. Tim is a co-author of the Nature paper.

"This is a great example where the classic scientific pursuit of palaeontology meets the space age.  This can only happen at a university where we have much greater freedom to follow our research wherever it leads. In tomography we use X-rays to take thousands of flat, 2D radiographs of the specimen at different views, then shoot them off to a super-computer, and get back a 20 Gbyte dataset that represents the specimen in glorious 3D.  Next comes the analysis and that's where the work really starts. Micro-tomography give scientists back the dimension they've been missing all these years - space. Micro-tomography is much more than just a 3D microscope - it gives us the chance to simulate lost creatures, new materials and even improve oil recovery. The work at the ANU on developing 3D analysis is leading edge and the focus of a new company to improve oil recovery."

Sir David Attenborough: (transcript from the live link to London)

On having the fish fossil named after him:

“I am very, very flattered and I am very undeserving. This fish was discovered in a marvellous place, in Gogo, Western Australia – I was very lucky to go there back in the 70s to see this site, where these extraordinary fossils are produced and are preserved in such a wonderful state that you can now look at the details of its anatomy including this fish which actually has a baby in the uterus. It is the first and earliest known vertebrate to have internal fertilisation and to rear its young with a placenta and with an umbilical cord. Now what I’ve done to deserve that, I really can’t imagine."

On visiting the Gogo site in the 70s when making “Life on Earth”

“I remember very well getting out of a helicopter and looking around at these nodules and picking one up and there, perfectly preserved was the most wonderful scute, a dermal scute, a bone from the top of the fish’s cranium.”

Professor Patricia Vickers-Rich is Chair in Palaeontology (School of Geosciences) and Founding Director of the Monash Science Centre Monash University Melbourne, Australia

"The spectacular announcement of internal fertilisation and viviparity in an ancient, now extinct, group of fishes (the ptyctodontid placoderms) is certainly worthy of its place in Nature this week.  It also points to the high quality of preservation typical of the Gogo locale, one of a few world class palaeontological sites in Australia.  It also highlights the determined and long term effort put into preparing and studying this material organized by Dr John Long and his students and team at the Museum Victoria and Monash University.  Congratulations to them all.  This new form with its tiny unborn babe is aptly named after a hero to all of us, David Attenborough (the new name is Materpiscis attenboroughi - the genus referring to the fish being a Mum!) - time for a new Doco David!"

Dr Steven Salisbury is a lecturer at the School of Integrative Biology, University of Queensland.

"This is a spectacular discovery that has important implications for our understanding of the evolution of live-bearing in vertebrates.  Live-bearing has evolved numerous times among fishes, most notably sharks and rays, so its recognition in placoderms such as Materpiscis is not surprising.  The large size of the embryo relative to the mother indicates that the young of this fish were born well-formed; a strategy that may have evolved to counter predation from other larger fishes.

The discovery is a credit to Long and his colleagues for the obvious attention to detail that was paid to the specimen during laboratory preparation. It is very likely that the specimen would have been overlooked had it been discovered and prepared by most commercial collectors. The science, and therefore the value to the public, would have been lost.  It highlights the need for further legislation to monitor the collection of fossils in Australia.  They are a unique part of our country's natural heritage, and as such need to be properly conserved.  380 million years in the making is a long time."

Dr Alex Ritchie is Research Fellow of Palaeontology at the Australian Museum.

“The Late Devonian Gogo Formation of the Kimberley area, NW Australia, is world-famous for its beautifully preserved fossils of long-extinct fishes that lived and died there 380 million years ago. After 40 years of intensive searching, the Gogo fossil sites still produce surprises, as illustrated by a spectacular discovery reported in this week’s ‘Nature’.  The delicate skeleton of a small armoured fish, painstakingly and skilfully etched by Australian scientists from a limestone nodule, was found to contain a unique and unexpected feature – a single large embryo still connected to the mother by a mineralised umbilical cord. Clearly this baby would have been born alive if the mother had survived. This remarkable fossil provides us with by far the oldest record of live birth in backboned animals and reveals that some early armoured fishes had already developed a very advanced mode of reproduction, not unlike some modern sharks and rays. In a particularly elegant touch the name of the new genus reflects its maternal role and the species name honours the world’s most respected natural history communicator.”

Dr Sue Turner is an honorary Senior Research Associate at the School of Geosciences at Monash University.

“When one animal is found coincident with another in the fossil record there are only a few possible interpretations, either they just happened to be in the same place at the same time, or one had eaten the other, or when the two specimens are apparently of the same species but significantly different in size, as in Long and his colleagues, Trinajstic, Young and Senden's remarkable revelation in 'Nature', then you might conclude that you can see a baby inside a mother.

This exciting discovery of a placoderm embryo also with a fossilised umbilical connection to its mother from the wonderful GOGO nodules from the Kimberley region of northwestern Australia does indeed seem to support the case for the reproductive strategy of viviparity (bearing live babies) associated with internal fertilisation as originating early within these vertebrates.

We now must look harder further back in time and there are many microfossils of young (baby) placoderms earlier in the Devonian, but as yet no definitive earlier fossils to show the sex of the animals.”