Slow-cooking dinosaur eggs may have contributed to extinction, say scientists
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Wednesday, January 4, 2017
A joint research team from the University of Calgary, American Museum of Natural History, and Florida State University announced on Monday that the eggs of non-avian dinosaurs such as the duck-billed dinosaur took as long as six months to hatch, far longer than had previously been believed.
| We could literally count [the growth rings] to see how long each dinosaur had been developing. | ||
Bird eggs incubate for 11 to 85 days, about half the time of most other egg-laying vertebrates. Scientists had thought dinosaur eggs were more like those of modern birds than modern reptiles, but this long hatch time is far more reminiscent of monitor lizard than magpie.
The scientists reached this conclusion by comparing CT scans of the teeth of dinosaur embryos of two different species, the Protoceratops andrewsi, which had eggs weighing under 200 grams, and Hypacrosaurus stebingeri, a type of duck-billed dinosaur that had eggs twenty times that size. They observed the von Ebner lines, patterns that form in vertebrate teeth as they grow, to determine how long the overall developmental process was taking. “They’re kind of like tree rings, but they’re put down daily,” said Florida State University co-author Gregory Erickson. “And so we could literally count them to see how long each dinosaur had been developing.” They found the Protoceratops embryo was about three months old and the Hypacrosaurus about six months.
According to the research team, this may be one reason why dinosaurs did not recover after the Cretaceous-Paleogene extinction event 65 million years ago. Both the eggs and any parents guarding them would have drawn the attention of predators and been unable to flee floods or other problems. Guardians might not have been able to move far to find food. This, researchers say, would have put dinosaurs at a disadvantage over animals with quicker-hatching eggs and their mammalian competitors.
Natural History Museum Curator and study co-author Mark Norell cites advances in imaging technology as the reason why this study is being published today: “We know very little about dinosaur embryology, yet it relates to so many aspects of development, life history, and evolution, [b]ut with the help of advanced tools like CT scanners and high-resolution microscopy, we’re making discoveries that we couldn’t have imagined 20 years ago.”
The research team plans to study more fossilized dinosaur embryo skeletons to confirm their findings. Specifically, the current study did not include the skeleton of a velociraptor or any other dinosaur considered closely related to birds.
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Interview with BBC Creative Archive project leader
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Thursday, June 22, 2006
The Creative Archive project is a BBC led initiative which aims to make archive audio and video footage available to be freely downloaded, distributed, and ‘remixed’. The project is still in a pilot stage, and is only available to UK residents, but the long-term future of the project could have a major impact on the way audiences interact with BBC content.
The project is partly inspired by the Creative Commons movements, and also by a general move within the BBC to be more open with its assets. Additionally, educational audiences such as schools have expressed an interest in using BBC content within the classroom, both to watch and to create multimedia content from.
So far, clips made available under the licence have included archive news footage, nature documentary footage, and video clips content designed for educational uses. “It’s done very well with the audiences we’ve directed them towards – heavy BBC users,” says Paul Gerhardt, project leader. Users downloading the clips are also prompted to fill in a questionnaire, and so far 10-15% of people seem to be doing something with the material, although the BBC can’t be sure what exactly that is.
One of the biggest limitations within the licence as it currently stands during the pilot scheme is that the material is only available for use by people resident in the UK. The BBC’s Creative Archive sites use ‘geo-IP filtering’ to limit downloads to the UK, but there is some confusion over whether people who create their own content using the material can upload their creations to their own websites. A question within the FAQs for one of the more recent selections of clips suggests that this isn’t possible, saying “during this pilot phase material released under the terms of the Creative Archive Licence cannot be used outside the UK – therefore, unless a website has its use restricted to the UK only, content from the ‘Regions on Film’ archive cannot be published on it.”
“We want people to make full use of this content, whether they cut and paste it or whether they share it, and we completely accept that we’ve got a bit of a contradiction at the moment by saying UK-only and yet encouraging people to put it on their sites to share it with others, because you can’t expect people to have geo-IP restriction technology,” admits Mr Gerhardt. “We’re thinking hard about how to deal with this after the pilot – at the moment it’s quite likely that we’re probably going to need to find a distribution partner outside of the UK, so that if you’re outside of the UK you’ve got roughly the same experience as in the UK, but the content could be surrounded by sponsorship messages or advertising or whatever. Once we’ve done that then leakage from one to the other won’t really matter very much.”
The Creative Archive project has not been without critics from the commercial sector, worried that the BBC giving away their content for free would make it difficult for them to be able to make money from their own content. The BBC has explained to some of the commercial players that the content would be limited during the pilot, would not be available in broadcast quality, and that watermarking technologies would be trialled so that content could be recognised when it crops up elsewhere. The BBC is also investigating a business model for the future where there would be a “close relationship between public access to low-resolution content and a click through to monetising that content if you want to buy a high-resolution version”. People who want to play around with the material might discover they have a talent and then find they need to get a commercial license to use it properly, Mr Gerhardt explains, and the project wants to make it easy for this to happen.
Before the project can go ahead with the full scale launch, it will have to go through a ‘public value test’ to assess its overall impact on the marketplace, and commercial media companies will have a chance to input at this point.
For ease in clearing the rights, all of the content available under the pilot project is factual, but in the future the project could include drama and entertainment content. The BBC may also, in the future, work the Creative Archive licences into the commissioning process for new programmes. “This raises some really interesting ideas – if you have a documentary series, you could use the Creative Archive to release the longer form footage, for instance – that would create a digital legacy of that documentary series,” Mr Gerhardt explains. “The other interesting thought in the longer term would be for the BBC, or another broadcaster, to contribute to a digital pool of archive material on a theme, and then invite people to assemble their own content out of that. We could end up broadcasting both the BBC professionally produced programme accompanied by other programmes that other people had made out of the same material.”
One of the ways that the Creative Archive licence differs from the other ‘copyleft’ licences like Creative Commons, aside from the UK-only limitation, is that the licence currently allows the BBC to update and modify the licence, which may worry those using the licence that their rights could suddenly become more restricted. “The licence at the moment is a draft, and we’ve given warning that we may well improve it, but we wouldn’t do that more than once or twice. The ambition is that by the time we scale up to the full service we would have a fixed licence that everyone was comfortable with, and it wouldn’t change after that.”
“The ambition is to think about creating a single portal where people can search and see what stuff is out there under the same licence terms, from a range of different suppliers. The idea is that if we can create something compelling like that, we will attract other archives in the UK to contribute their material, so we’d be aggregating quite a large quantity.”
The Creative Archive project has captured the interest of many Internet users, who are growing increasingly, used the idea of being able to ‘remix’ technologies and content. Some groups have been frustrated with the speed at which the project is developing though, and with some of the restrictions imposed in the licence. An open letter to the BBC urges the dropping of the UK-only limitation, the use of ‘open formats’, and to allow the material to be usable commercially.
Mr Gerhardt has publicly welcomed debate of the licence, but makes it clear to me that the whole BBC archive will never all be available under the Creative Archive terms. “We will make all our archive available, under different terms, over the next five to ten years, at a pace to be determined. There would be three modes in which people access it – some of the content would only be available commercially, for the first five year or so after broadcast, say. The second route is through a ‘view again’ strategy where you can view the programmes, but they’d be DRM-restricted. And the third mode is Creative Archive. Over time, programmes would move from one mode to another, with some programmes going straight to the Creative Archive after broadcast.”
Others who disagree with the ‘UK-only’ restriction within the licence include Suw Charman, from the Open Rights Group, who has said “it doesn’t make sense in a world where information moves between continents in seconds, and where it is difficult for the average user to exclude visitors based on geography.” On the project generally, though, she said “I think that it is a good step along the way to a more open attitude towards content. It is a toe in the water, which is far preferable to the attitude of most of the industry players, who are simply burying their heads in the sand and hoping that lawsuits and lobbying for new legislation will bolster their out-dated business plan.”
Other organisations currently participating in the Creative Archive scheme include the British Film Institute, the Open University and Teachers’ TV. Two artists have been awarded scholarships to create artworks using BBC archive material, and BBC Radio 1 has held a competition asking people to use the footage in creative ways as backing visuals to music. The process of making the BBC’s archive material fully available may be a long one, but it could end up changing the way that people interact with the UK’s public service broadcaster.
