Resurrecting dinosaurs with medical scanners and 3D printers

CT scans and 3D printers are making it possible to see fossils that were previously inaccessible inside rock.

Accurate copies of fossilised bones can now be made from the combined use of computed tomography (CT) scans and 3D printers, according to a paper published in the journal Radiology.

The technique offers scientists a non-destructive way of transporting and handling rare or fragile fossils.

To protect such specimens from damage during transportation, the fossils are often stored in plaster jackets or casts. These jackets must be strong enough to protect the fossils, but should also separate easily from the specimen when removed.

It is during the removal of the plaster and surrounding sediment that the fossil is in danger of material loss or even destruction. This typically occurs when the plaster is stuck fast to the bone.

(A 3D print of a fossil (right) next to the original still inside a plaster jacket. Image: Courtesy of Radiology and RSNA)

A group of German researchers found that, by using CT and 3D printers, they could separate fossilised bone from its surrounding sediment matrix in a way that would not harm the specimen, then produce a 3D copy of it.

Applying this method to an unidentified fossil from the Museum für Naturkunde in Berlin, the researchers scanned the bone with a 320-slice multi-detector system to show up the different attenuation (absorption of radiation) through the bone and the surrounding sediment matrix, depicting clearly the fossilised vertebra.

The scan also provided information on the condition and integrity of the specimen, like otherwise unknown fractures, and helped the researchers build an accurate reconstruction of the fossil.

Then using a laser sintering system – a process which uses high-powered lasers to fuse materials by adding thin horizontal layers of plastic – an accurate 3D copy of the fossil was produced.

(An enlarged 3D copy of a 380 million year old coelacanth skull found near Fitzroy Crossing, Western Australia. Image: John Long)

The impact on palaeontology
According to Richard Brian Gunderman, a professor of radiology at Indiana University who was not involved in the study, CT scanners are able to determine the exact structural dimensions of an object, down to fractions of a millimetre.

This data can then be used to construct a replica so precise that objects of great historical interest, like Stradivarius violins, have been created to sound remarkably similar to the originals.

“Such a technology has been a boon to palaeontologists in the past few years,” said John Long, strategic professor in palaeontology at Flinders University.

“Once we relied on meticulous time-consuming methods to prepare delicate fossils out of the rock and, even then, we could only see their external features. Now, using high-resolution micro-CT scanners and synchrotrons [particle accelerators], we can investigate every nook and cranny of the fossil right down to individual cells and tissue structures without having to risk damaging the specimen.

“Combined with advanced 3D printing, we can now slice though the ancient fossil skulls and print them in halves showing the full anatomy in clear definition. This will no doubt revitalise palaeontology.”

(A 3D scan of a 380 million-year-old Gogonasus fish skull by Tim Senden and ANU Vizlab.)

Ahi Sema Issever, from the Charité Campus Mitte in Berlin and one of the study’s authors, explained: “The most important benefit of this method is that it is non-destructive so the risk of harming the fossil is minimal. In addition, not only does this method allow for a global exchange of rare fossils in any quantity, data on the specimens can also be digitally shared between research institutes, museums and schools while protecting the original fossil.”

Darren Curnoe, associate professor at the University of New South Wales, agreed, saying: “Famous fossils like the Taung Child in South Africa - the very first ancient ape-like creature found in our human evolutionary tree - has been quite badly damaged following almost 90 years of study by scientists.

“Almost everyone who sees the fossil wants to take a couple of measurements of their own, and by doing so, is damaging these priceless pieces of our collective heritage. We need to do better, and such technology might just be the answer.”

A note of caution
Although supportive of the technological breakthrough in this study, Professor Long warned that researchers must not rely too heavily on tomographic imagery and 3D printing to draw their conclusions.

“It is important to carefully study the preservational biases of the original fossil first to determine how reliable a computer-generated image will be. In some cases, replacement of bone by other minerals or the presence of solid inclusions can effect the quality of CT images and affect 3D printing results.

“Scientists still need to study the original specimens in detail first, and then make interpretations using CT tomography and 3D printing.”

(A scanned 400 million-year-old placoderm eye capsule found in Taemas near Canberra. Image: Tim Senden)

Associate Professor Curnoe agreed, saying: “Any model made from CT scans must properly distinguish actual bone from missing bone, or even from materials like plaster, that had been used in the past to reconstruct missing bones in the fossils. This is particularly important since most fossils found are incomplete or distorted.

“In the end, there is nothing like seeing the real thing to fully understand the anatomy and the state of preservation of a fossil. But, for the sort of work many scientists do, especially postgraduate students, 3D models would be incredibly useful at a time when funding can be very hard to get.”

Beyond fossils
Some experts speculate that the findings from this study will benefit the medical field, like building and fitting implants in orthopaedic surgery. Others feel that the technique could be used to model real bones and other tissues, such as cadavers that have been preserved in ice or peat bogs.

Martin Baumers, a research fellow at the University of Nottingham, would like to see the implementation of a virtual library and data infrastructure for such 3D data and designs. He believes that it would aid collaborative research, allowing experts from different disciplines to share and retrieve 3D models for 3D printing or other scientific, even commercial, usage.

For Professor Long, the biggest breakthrough will come when palaeontologists possess the ability to make portable machines to take into the field and scan fossils, still buried under the rock layers, to determine the full extent of the fossil before excavating it.

This article was originally published at The Conversation. Read the original article.The Conversation

A scan of a 380million-year-old tooth from a fossil shark. (Image: Tim Sendon)
YouTube
Show Hide image

"It's just a prank, bro": inside YouTube’s most twisted genre

Despite endless headlines and media scrutiny, catchphrases such as "it was a social experiment" and "block the haters" have allowed YouTube's dangerous pranking culture to continue unregulated. 

A year and five months after the worst prank video ever was uploaded to the internet, its crown has been usurped. In November 2015, YouTuber Sam Pepper made headlines after he filmed a video entitled “KILLING BEST FRIEND PRANK”. In the video, Pepper kidnaps a man before forcing him to watch his friend be “murdered” by a masked figure. Rocking on the chair he has been tied to, the victim sobs and shouts: “We’re just kids”.

Last week, an actual child – aged nine – was victim to a similarly distressing “prank”. Michael and Heather Martin, of the YouTube channel DaddyOFive, poured disappearing ink on to their son Cody’s carpet before – in Heather’s words – “flipping out” on the child.

“What the fuck did you do,” yells Heather to summon Cody to his room. “I swear to God I didn’t do that,” screams and cries Cody as his parents verbally berate him. His face goes red; he falls to his knees.

You won’t find either of these videos on either of their creators’ channels today. After considerable backlash, Pepper deleted his video and DaddyOFive have now made all of their videos (bar one) private. The Martins have faced international scrutiny after being called out by prominent YouTuber Philip DeFranco, who collated a video of clips in which Cody is “pranked” by his family. In one, Cody appears to be pushed face-first into a bookcase by his father. In another, a visibly distressed Cody sobs while his father says: “It’s just a prank bro.”

These five words have been used to justify some of the most heinous pranks in YouTube history. Sam Pepper famously called a video in which he pinched the bottoms of unsuspecting women, a “social experiment”. Usually, though, creators’ excuses follow a pattern. “It was just a prank,” they say. Then, if the heat doesn't subside: “Actually, it was fake.”

Three months after his “KILLING BEST FRIEND” prank, Pepper claimed the video – and all of his other prank videos – were staged. In a video entitled “Family Destroyed Over False Aquisations [sic]” the Martins have now also claimed that their videos are scripted. “We act them out,” says Michael. It seems many on the internet remain sceptical. The Child Protection Services website for Maryland – where the Martins live – has crashed after Redditors encouraged one another to report the family. If the Martins’ videos are indeed staged, Cody is one of the shining child actors of our time.

Though the Martins might yet face severe consequences for their pranks, it wouldn’t be surprising if they didn’t.  The “Just a prank”/“No it’s fake” cycle means that despite multiple headline-grabbing backlashes, YouTube pranking culture continues to thrive. Boyfriends pretend to throw their girlfriend’s cats out windows; fathers pretend to mothers that their sons have died. YouTubers deliberately step on strangers' feet in order to provoke fights. Sometimes, yes, pranksters are arrested for faking robberies, but in the meantime their subscribers continue to grow in their millions.

At present, there is no regulatory body that examines YouTube. Pranksters who break the law are arrested, but children whose daily lives are filmed for the site are not protected by the same regulations that safeguard child actors from being overworked or exploited. Though the communications authority Ofcom has guidelines about wind-up calls and consent, it does not regulate YouTube. The BBC were famously fined £150,000 by the body after Russell Brand and Jonathon Ross prank called Andrew Sachs, yet internet pranks remain out of its jurisdiction.

Though YouTube removes videos that breach its “Community Guidelines”, it seems illogical that we trust the service to police itself. Since the invention of the radio, we have assumed that independent bodies are needed to scrutinise the media – so why you should the largest video-sharing platform on the planet be exempt? No one is truly looking out for either the pranking victims or the children of YouTube. God forbid, like Cody, if you are both.

It is also arguable that YouTube pranks need more regulation than those broadcast on TV. Britain’s favourite pranking shows revolve around humiliating comedians themselves – Trigger Happy TV, Balls of Steel, Jackass – or are very soft (think a man pretending to be both a mime and a policeman) in nature. When someone is outright humiliated on TV, it’s because they are seen to be “fair game”, such as in Comedy Central’s Fameless Prankers, where people desperate to be famous are forced into increasingly humiliating situations. On YouTube, there are no consent forms or waivers to ensure filming remains ethical, and YouTube pranksters often target more vulnerable people.

“There’s an element of power here with the parents and it seems this is very top-down,” says Jonathan Wynn, a sociology professor at the University of Massachusetts who has written on pranks in the past. Wynn explains that traditionally pranks mock status and hierarchy, such as when court jesters taunted kings. When pranks come from the top down, Wynn says they allow a group to bond emotionally – arguably something the Martins are attempting as a family. Nonetheless, Wynn notes this would work better if the children also pranked their parents equally. “In this case the status differential is quite high, when you have children and parents.”

Traditionally, the mainstream media has had little room for this type of content. In 2012, two radio DJs attempted to prank the Duchess of Cambridge Kate Middleton by calling the hospital she was staying at, but instead tricked two nurses. When one of these nurses, Jacintha Saldanha, died by suicide days later, the episode seemed the ultimate illustration of the recklessness of pranks that “punch down”.

Conversely, status differentials are a large part of YouTube prank culture. Rather than attacking people in power, YouTube pranks are often played by those in power (the YouTube famous) on those who have lower social status. Frequently, boyfriends prank girlfriends, for example, and since 2014, white pranksters have filmed “in the hood” pranks provoking young black men. In “The N Word Prank!!” famous internet prankster Roman Atwood goes around saying “What’s up my neighbour” to people of colour, knowing that it will be misheard as a racial slur. In the context of this pranking culture, a parent pranking a child to the point of tears seems almost inevitable.

Perhaps, then, it is easy to understand why Michael and Heather Martin “prank” their children – it is harder to understand why anyone is watching. The DaddyOFive channel has over 750,000 subscribers, with over 7,000 of these subscribing after Philip DeFranco’s video accused the family of “abusing” their children. In order to defend themselves, the Martins initially employed another YouTube rhetoric, on top of “just a prank bro”. In a since deleted video, they invited their fans to “block the haters”.

This phrase is ingrained in online culture, and has allowed internet celebrities to dismiss criticism for years. By painting anyone who is critical as “jealous” or a “hater”, YouTubers can ensure their fans ignore their words and therefore stay loyal. In a video response to Philip DeFranco, the Martins riffed off a popular meme and placed spoons over their eyes to symbolise this mentality, and now fans as young as 12 are copying this action to show their support. When I search the hashtag used by the family’s supporters to see if anyone might be willing to explain why they still love the channel, I am faced with the reality that most of DaddyOFive’s fans are children. Though YouTube’s minimum sign-up age is 13, there is nothing really stopping children from watching – and normalising – harmful content, particularly when it is disguised as a “prank”.

In this context, it doesn’t matter in the slightest whether a prank is faked. Sam Pepper might have asked his friend's permission before he fake-kidnapped him, and perhaps Michael Martin was only pretending when he pushed his son into a bookcase. Neither of these facts will prevent children – 19 percent of whom have a desire to be famous – from copying these actions in order to promote their own YouTube channels. Even if a YouTuber is punished for a dangerous pranking video, there are thousands of other pranksters ready and willing to take their place. 

It remains to be seen whether the Martins will continue with their YouTube channel. At the end of their now infamous invisible ink prank, Michael asks Cody to “do the outro” – the concluding section of a YouTube video. Wiping his nose and still red in the face, Cody rattles off his script at alarming speed.“Thank you guys for watching this video if you like this video and want to see more videos like this one leave a comment down the section below and don’t forget to follow us on Twitter, Instagram, Facebook, Snapchat… and don’t forget to… Like and Subscribe.” 

Since the backlash, Michael has added a new line into the “About” section of the DaddyOFive YouTube channel. After reiterating that the videos are fake, he writes: “no child was harmed in the making of our videos”. 

Amelia Tait is a technology and digital culture writer at the New Statesman.

0800 7318496