New algorithm for estimating body mass of extinct quadrupedal mammals

first_img Ever since humans discovered that there were creatures roaming the earth that had gone extinct, efforts have been made to try to imagine what they must have looked like. Skeletons have been reassembled and then estimates on body shape and mass were made based on how modern animals are put together—but such efforts have been deemed too open to interpretation, which likely meant that researchers were simply guessing. In an attempt to improve the accuracy, other researchers developed 3D computer models and simulations, but have had to acknowledge that there was still a lot of guesswork involved. Now, in an attempt to remove some of that guesswork, Brassey and Gardiner have developed a computer algorithm that takes advantage of the best aspects of both prior methods. Their algorithm allows for the creation of what they call “alpha-shapes” where objects meant to mimic actual body parts, are “shrink-wrapped” around a reconstructed virtual skeleton created from the actual bones of a real specimen. The algorithm also allows for fine-tuning the shrink wrapping process from very fine, to quite coarse—on an individual specimen. Once the rendering is done, the algorithm calculates the original body mass of the creature by using an average of the body mass of 14 modern animals.Brassey and Gardiner have tested their algorithm on the remains of a found wooly mammoth and a giant sloth—the first was calculated to be 3.6 metric tons, the second 3.7. They note that the reconstruction of the skeleton has a big impact on the final result, which means that in order to get an accurate body mass estimate, researchers must first put the skeleton together in the way that nature intended. More information: An advanced shape-fitting algorithm applied to quadrupedal mammals: improving volumetric mass estimates, Published 19 August 2015.DOI: 10.1098/rsos.150302AbstractBody mass is a fundamental physical property of an individual and has enormous bearing upon ecology and physiology. Generating reliable estimates for body mass is therefore a necessary step in many palaeontological studies. Whilst early reconstructions of mass in extinct species relied upon isolated skeletal elements, volumetric techniques are increasingly applied to fossils when skeletal completeness allows. We apply a new ‘alpha shapes’ (α-shapes) algorithm to volumetric mass estimation in quadrupedal mammals. α-shapes are defined by: (i) the underlying skeletal structure to which they are fitted; and (ii) the value α, determining the refinement of fit. For a given skeleton, a range of α-shapes may be fitted around the individual, spanning from very coarse to very fine. We fit α-shapes to three-dimensional models of extant mammals and calculate volumes, which are regressed against mass to generate predictive equations. Our optimal model is characterized by a high correlation coefficient and mean square error (r2=0.975, m.s.e.=0.025). When applied to the woolly mammoth (Mammuthus primigenius) and giant ground sloth (Megatherium americanum), we reconstruct masses of 3635 and 3706 kg, respectively. We consider α-shapes an improvement upon previous techniques as resulting volumes are less sensitive to uncertainties in skeletal reconstructions, and do not require manual separation of body segments from skeletons. Restoration of a steppe mammoth. Credit: Kurzon/Wikipedia, CC BY-SA 3.0 Explore further Museum workers able to digitally recreate Stegosaurus to find its mass © 2015 Tech Xplorecenter_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. A pair of researchers, one with the University of Manchester, the other with the University of Salford, both in the U.K., has developed a new computer algorithm for estimating the body mass of extinct quadrupedal mammals. In their paper published in Royal Society Open Science, Charlotte Brassey and James Gardiner describe how they came up with the new algorithm and the ways that they believe it can be used to improve estimates of body mass of extinct creatures. Journal information: Royal Society Open Science Citation: New algorithm for estimating body mass of extinct quadrupedal mammals (2015, August 19) retrieved 18 August 2019 from https://phys.org/news/2015-08-algorithm-body-mass-extinct-quadrupedal.htmllast_img

Derrick Rose steals the show LeBron Cavs take the game

The Cleveland Cavaliers and Chicago Bulls meet for an NBA preseason game Oct. 20 at the Schottenstein Center. Cleveland won, 107-98. Credit: Mark Batke / Photo editorEven though it wasn’t a regular season game, NBA action at the Schottenstein Center was in full swing as the Cleveland Cavaliers defeated the Chicago Bulls on Monday night, 107-98.The player many people undoubtedly came to see — Cavs forward LeBron James — did not disappoint as the Akron native totaled 18 points on 6-of-11 shooting to go along with seven rebounds and six assists in 32 minutes of play.James said playing in front of the Central Ohio crowd was special.“It was great, it was great to be here. It is great to have these fans and for us to put on a show for them,” James said.Cavaliers coach David Blatt said even though it was an exhibition game, he thought the matchup was played at a high level.“It’s no big thing, obviously this is just an exhibition game, but certainly a good level game for fans to see,” Blatt said. “We had a full crowd here in Columbus, and the people got their money’s worth and both teams played hard and played pretty well.”Get their money’s worth they did, as the Cavs weren’t the only ones putting on a show for the sellout crowd of 19,049.Bulls guard Derrick Rose, who has missed nearly two full seasons because of multiple knee injuries, exploded for 16 points in the second quarter, bringing the crowd at the Schottenstein to its feet multiple times. He totaled 30 points on 12-18 shooting for the game despite only playing 24 minutes.James said although Rose dissected the Cavs defense for most of the night, he was happy and unsurprised to see the former Memphis Tiger playing to his ability again.“I watched him all summer. Watched him in their practices when they were in Vegas, and I payed attention to him over the preseason,” James said. “As a league, as a fan, it is great to have him back and him playing at a high level.”Blatt said he agreed with his star forward and commented on how tough it is to stop Rose.“Do you have any ideas? I dont know what to do with that guy,” Blatt said following the game. “He is pretty good. As a basketball person, and as a lover of this sport, it was great to see him back.”Rose’s point-guard counterpart — the Cavaliers’ Kyrie Irving — also impressed, as the Duke product finished with a team-high 28 points on 10-of-19 shooting to go along with seven assists in 39 minutes of play.Cleveland newcomer and former Minnesota Timberwolves’ player Kevin Love struggled with his shot against the Bulls as he finished 2-for-10 from the field and was the only Cavaliers starter who didn’t score in double figures with just nine points to finish.Despite Love’s struggles, James said it was good to get extended minutes with Love and Irving for the first time during the preseason.“We have limited time on the floor, but I think tonight was a good example of what we can do,” James said. “That was the closest to 48 minutes we have played in the preseason. Kyrie played a great game, Kev’s shot was off a little bit, but I think he had a great game with 13 rebounds.”Cavaliers center Anderson Varejao picked up the slack as he came out firing on all cylinders in the first half. He scored 16 points on 8-of-10 shooting to help boost Cleveland to a 51-49 halftime lead. He finished with 22 points on the night.Blatt said following the game that he was pleased with how his team performed as a whole.“What I really liked obviously about tonight was that we had Kevin, Kyrie, LeBron on the floor at the same time,” Blatt said. “We got a fair view of that tonight, and I thought that went pretty well. Overall, I think the Cavaliers are taking strides in the correct direction.”The Cavaliers are set to play their preseason finale Wednesday against the Memphis Grizzlies at the FedExForum in Memphis before they are scheduled to begin their regular season at home Oct. 30 against the New York Knicks.

L.A. council seeks phone-users tax

By Beth Barrett STAFF WRITER Setting up a showdown with voters, the Los Angeles City Council unanimously declared a revenue emergency Tuesday and agreed to ask voters to approve a 9 percent telephone-users tax that would expand the levy to many new technologies. The 14-0 vote to place the tax on the February presidential primary ballot comes amid concern that a judge could soon invalidate the current 10 percent phone tax – which brings in $270 million of the city’s $7 billion budget. AD Quality Auto 360p 720p 1080p Top articles1/5READ MOREGame Center: Chargers at Kansas City Chiefs, Sunday, 10 a.m.Councilmen Dennis Zine and Greig Smith, who had questioned the urgency of the measure, met privately with Mayor Antonio Villaraigosa after learning – to their surprise – that the measure would tax new technologies like VoIP and private communication services used by large companies. They then voted for the measure – providing the unanimous support needed to get it on the February ballot and allow it as an emergency to pass with only 50 percent support instead of the two-thirds majority required for taxes. The council’s decision brought immediate criticism over expansion of the tax as well as the city’s belated recognition that the current phone tax probably violates taxpayer protections imposed by Proposition 218. City officials estimate the proposed tax – which supporters intend to promote as a 10 percent cut – would raise about $243million annually. They said they don’t have estimates on how much the new taxes on “emerging” technologies will raise. The communications industry challenged the current telephone-users’ tax after the federal government last year backed off a tax that the city had referenced since 1967. Earlier this month, Villaraigosa released a report recommending the city take “emergency” action to place the tax on the ballot. A unanimous council vote was needed to declare an emergency and put the measure on the ballot, but Smith and Zine expressed strong criticism. They questioned the urgency of the measure as well as whether it should include a higher voter-approval requirement. On Tuesday, Zine expressed additional concern and called it “creative taxation.” He also criticized several exemptions, including a 5 percent rate for telemarketers. “I’m of the belief (the proposal) should be candid and forthright, not smoke and mirrors, bait and switch,” Zine said in an interview before the vote. But Zine and Smith flip-flopped after holding a last-minute private meeting with Villaraigosa, saying he convinced them that the city would be in serious financial trouble without the tax. “We can’t be fiscally irresponsible,” Zine said, adding that public safety and other services could be slashed without the tax revenue. Smith said that in the closed-door meeting, the mayor argued for the tax – including its expansion to new technologies – and was upset the council hadn’t gotten a more complete briefing earlier. City Administrative Officer Karen Sisson, the mayor and Councilman Bernard Parks, chair of the Budget and Finance Committee, all defended taxing new communications technologies. “Everyone who makes a phone call should be treated equitably,” Sisson told the council. Parks said the city always has made efforts to capture new technology within the tax base. Cell phone service, for example, now accounts for about $162 million of the $270 million in annual telephone tax revenue. “You just move so the tax base continues to grow,” Parks said. Still, despite the expansion of tax to new services, the vast majority of phone users should see a reduction in taxes, insisted Matt Szabo, the mayor’s spokesman. “The loss of $270 million would have a devastating effect on critical services. The mayor believes the voters should have an opportunity to vote on critical services while lowering their phone tax,” Szabo said. Exemptions in the measure, meanwhile, also will be reviewed and could be changed at a later election. Chief Legislative Analyst Gerry Miller said raising the rates now would offset the message that the tax is being reduced. Councilman Richard Alarcon worried that taxing telemarketers at their current 5 percent rate could doom the measure with voters. Business and other groups also criticized the action, which follows the city’s recent negotiation of a five-year contract that gives most municipal workers a nearly 23 percent raise at a cost of over $200 million. Transfers worth tens of millions of dollars to the city’s general fund from the Department of Water and Power also are in jeopardy pending a court action. Bob Stern, president of the Center for Governmental Studies, said taxing new technologies would make up for some of the touted rate cut. “Obviously they’re looking for new forms of revenue by people who don’t have as much of a lobbying arm,” Stern said. Kris Vosburgh, executive director of the Howard Jarvis Taxpayers Associations, said whether the measure actually cuts taxes is questionable. In a memo to council members, Sisson said loss of the tax would likely mean a combination of cutting services, raising fees and laying off employees. “Potential service reductions will involve several essential services in the areas of public safety, community services, recreation and cultural programs, transportation services and general city support,” the memo read. Of the city’s $6.8 billion budget, only about $3.6 billion is considered unrestricted to pay for various services, with the telephone-users’ tax accounting for about 6 percent of that. “Every resident would feel it in some shape or fashion,” she said. beth.barrett@dailynews.com 160Want local news?Sign up for the Localist and stay informed Something went wrong. Please try again.subscribeCongratulations! You’re all set!