The great whales are carnivores, feeding on tiny, shrimp-like animals such as krill. Moreover, the microbes that live in whales’ guts — the microbiome — resemble those of other meat-eaters.But scientists now have evidence that the whale microbiome shares traits with that of creatures not known to eat meat: cows.Scientists led by Peter Girguis, professor of organismic and evolutionary biology at Harvard, have found that the gut microbiome of right whales and other baleen species shares characteristics with those of both cows and meat-eating predators. The dual microbial communities allow whales to extract the most nutrition possible from their diet, digesting not only the copepods they eat, but their chitin-rich shells as well. The study is described in a Sept. 22 paper in Nature Communications.Among the co-authors of the paper are James McCarthy, professor of biological oceanography and Alexander Agassiz Professor of Biological Oceanography in the Museum of Comparative Zoology; Annabel Beichman ’14, now a graduate student at the University of California, Los Angeles; Joe Roman from the University of Vermont; Jarrod Scott and David Emerson, both from the Bigelow Laboratory for Ocean Sciences in Maine; and Jon Sanders, a former graduate student in Girguis’ lab.“From one point of view, whales look like carnivores,” Girguis said. “They have the same kind of microbes that we find in lions and tigers that have very meat-rich diets. But they also have abundant communities of anaerobic bacteria, similar to those that [animals] use to break down cellulose.“However, there’s not a lot of cellulose in the ocean, but there is a lot of chitin, which is in the exoskeletons of copepods that baleen whales eat,” Girguis continued. “What our paper suggests is the whale foregut is much like a cow’s gut, and we posit that chitin-degrading anaerobic microbial community thrives in there, breaking down that material and making it available to the whale.”Those exoskeletons, Girguis said, represent as much as 10 percent of the whale’s total food intake, and would otherwise simply be defecated. By allowing whales to access the nutrition in the chitin-rich material, whales are able to extract the greatest possible benefit from their diet.“It’s almost like a pre-adaptation,” he said “that may give them a differential advantage in harnessing energy from their food. The morphology of their gut comes from their ancestors, the very same ancestors to cows, camels, and others. It serves them well as carnivores because it allows them to maximally extract nutrition from their food.”Ultimately, Girguis said, the study addresses questions that reach beyond the guts of whales.“This is really a question of what we can call phylogenetic inertia,” he said. “Because what we’re really thinking about is: When you look at the microbiome of an organism, you can, to some degree, look back in time and see its ancestors, because organisms that are related to one another seem to have similar microbiomes.“But not all organisms that are related live in the same kind of environment,” he continued. “So the question is, how different does your environment need to be before it changes your microbiome? This is a fundamental question about the relationship between your ancestry versus your current environment.”Many such questions might not have been asked, Girguis said, were it not for then-undergraduate Beichman. The second author of the study, Beichman kick-started the study when she and Roman took on the unenviable task of following pods of right whales at sea and collecting samples of their feces to determine which microbes were present.“There’s no other way to get the fecal samples but to collect them from the ocean,” Roman said.“It was a thrill to set out each morning into uncertain weather to search for elusive right whales, then to extract and sequence DNA from our smelly trophies,” Beichman said. “It had always been my passion to use the latest advances in genetic sequencing technology to answer questions about species of conservation concern, and so I wanted to add a genetic component to the study.“Working with my advisers to conceive the research questions based on the scientific literature, collect fecal samples in the field, and carry out DNA sequencing and analysis gave me invaluable experience at every stage of the study,” she added. “We all had different theories as to what the whale gut community might look like. What none of us expected was to see so much divergence from terrestrial mammals, or these shared characteristics with both terrestrial carnivores’ and herbivores’ microbiomes.”“Given what we know about whales’ ancestry — that they’re related to ruminants [animals that get nutrients from plants by fermenting them in an early stage stomach], and that they still have a multi-chambered foregut — there were several things we might find,” Girguis said. “One hypothesis was that their microbiome would look like those of other meat-eaters like lions and tigers, and the foregut was just vestigial. The other hypothesis was that it allowed a different group of microbes to do something we hadn’t thought about. What we found was that whales have a microbiome that looks halfway like a ruminant and halfway like a carnivore.”“We’ve come to better understand the evolution of whales over the past few decades, and see where they fit on the evolutionary tree. But we have not understood the microbial changes that have allowed them to become one of the most successful groups of animals in the ocean,” said Roman. “This study helps explain that.”Going forward, Girguis and colleagues hope to sample the microbial community in whales’ stomach chambers, and to extend the study to toothed whales, which don’t have such chitin-rich diets. The team also has drawn interest from aquariums, which may be able to use information about the gut microbes in whales to better care for animals kept in captivity.“A lot of aquariums … they know when their whales are healthy or not, but they don’t always have a causal factor, and these gut microbes may be a big clue,” Girguis said. “As long as people keep whales in captivity, there is value in this type of research, because it can keep them as healthy as possible.”While the study may not provide a definitive answer to questions of phylogenetic inertia, it does suggest that some morphological features, if they can provide an advantage, are retained, despite dramatic changes in a creature’s environment.“We now have this snapshot that addresses this question of how a creature’s evolutionary past interacts with its microbiome, and how its diet today influences its microbiome,” he said. “The answer is … if that morphological feature, if it has value to a species, then it may well be something that’s capitalized on over evolutionary time.”
RelatedPosts COVID-19: NCAA to revoke erring airlines licence over non-compliance FRSC to Schools: We’ll arrest, prosecute drivers who flout COVID-19 rules Sanwo-Olu: We’re committed to fulfilling promises to Lagosians Europe’s top clubs could take a 20 per cent to 25 percent hit to their enterprise values because of the “unprecedented crisis” caused by the COVID-19 pandemic.A study conducted by KPMG revealed this, taking into account players’ devaluation as well as the performance of the largest listed teams in recent months. It then compared this with KPMG’s data collected earlier in the year.“… KPMG’s forecast of the devaluation of the football sector at the top end of the market is between 20 percent and 25 percent, when compared with our recently published results of clubs’ EV as of Jan. 1 in 2020,” KPMG’s global head of sports, Andrea Sartori, said in a statement.“Having said that… peak devaluations for individual clubs can range from 15 percent up to 30 percent.“This depends on the strength of a particular club’s balance sheet, level of debt, structure of revenue mix and dependence on player trading activities.“Obviously, each club’s situation and EV impact will need to be assessed individually upon availability of their 2019-2020 financial statements.” The study estimated that the squad value of French champions Paris St-Germain could drop by 25.4 per cent after Ligue 1 was cancelled in April.That figure would have been around 18 per cent if top flight action had returned from its enforced break.The other four of Europe’s “Big Five” leagues – England, Spain, Germany and Italy – have all resumed their seasons, but matches are being held without fans present in stadiums.Spanish giants FC Barcelona’s squad value could fall from an estimated 1.136 million euros ($1.28 billion) in February to 903 million euros – down 20.5 per cent, the study added.Manchester United’s squad value could drop by 13.8 per cent, while that of Bayern Munich faces a fall of 15.8 per cent. Reuters/NAN.Tags: COVID-19DeclineEnterprise ValuesEuropeFootball Clubs
Follow Will on Twitter @WillLaws In a game of wasted offensive chances caused by poor special teams play on both sides, USC turned in a superb game on defense and did just enough on offense to claim its third victory of the season in a sloppy 17-14 win over visiting Utah State.Doing their part · The USC defense, led by redshirt junior linebacker and team captain Hayes Pullard (10), continues its stellar start to the season. Against Utah State, Pullard had five tackles and two pass breakups. – Ralf Cheung | Daily TrojanA slew of penalties and missed opportunities prevented the Trojans (3-1) from turning the game into a rout in the fourth quarter, and the Aggies (2-2) hung around through the final minutes until USC’s defense punctured Utah State’s upset hopes by stopping quarterback Chuckie Keeton on a fourth-down scramble.“We wanted to keep [Keeton] in front of us and not let him get to the sidelines,” freshman safety Su’a Cravens said. “When I saw [Keeton] go down, I was thinking, ‘That’s exactly how we planned it.’”SCORING SUMMARYUSC opened up the scoring on its second drive of the game with a 1-yard run from redshirt sophomore tailback Tre Madden. Later in the second quarter, after a 55-yard scamper from Utah State tailback Joey DeMartino brought the ball to the USC 8-yard line, Keeton completed a slant route to a leaping Brandon Swindall to knot the score at seven apiece.The teams then traded three-and-outs before USC used its grinding, two-back system to temporarily open up the passing game for redshirt sophomore quarterback Cody Kessler. Seven consecutive runs — four from Madden, three from freshman tailback Justin Davis — preceded a third-down conversion from junior wide receiver Marqise Lee and a 30-yard touchdown pass to redshirt junior tight end Xavier Grimble, who sailed undetected past Utah State’s safeties on a picturesque seam route down the middle to give USC a 14-7 advantage.After halftime, the Aggies showcased the explosiveness that USC head coach Lane Kiffin had been wary of in practice all week. A nine play, 72-yard drive took just 3:23 off the clock and deadlocked the score at 14 midway through the third quarter, the first time USC had given up any points in the third quarter this year.But after that, USC’s defense held Utah State in check through the end of the game, and junior kicker Andre Heidari provided the game-winning points for USC via a 25-yard field goal with 13:35 remaining.NOT SO SPECIAL TEAMSOutside of redshirt sophomore punter Kris Albarado, who pinned the Aggies inside their 20-yard line five times, the play of USC’s special teams was certainly not a strength. Heidari missed a 46-yard field goal in the third quarter, and the return teams failed to engineer any game-breaking plays.But special teams were undoubtedly a larger issue for the Aggies. Utah State kicker Nick Diaz clanked a 37-yard field goal attempt off the right upright in the first quarter to keep the Aggies from cutting into USC’s 7-0 lead, marking the fourth consecutive game that the USC defense held its opponents scoreless in the opening quarter.The Aggies also averaged just 34 yards per punt, including a botched 12-yard punt that gifted the Trojans great field position at Utah State’s 24-yard line as the clock turned into the fourth quarter.USC seemed poised to put a touchdown on the board after a run by Madden and a reception by Grimble gave the Trojans a first-and-goal opportunity at the Aggies’ 8-yard line. But the Trojans only came away with Heidari’s field goal that edged the score to 17-14.OFF DAY FOR OFFENSEThe USC rushing attack led by Madden and Davis, which averaged 196 yards per game and 4.5 yards per carry before Saturday, could only muster 118 rushing yards and 3.0 yards per carry against the Aggies. Madden finished with 93 yards on 24 carries, snapping his streak of three games with 100-plus rushing yards.Kessler was 13-of-26 for 164 yards and one touchdown, and also fumbled shortly before halftime to deny the Trojans a chance to build up a multiple-possession lead.The Trojans were held out of the end zone in the second half after Utah State repeatedly put eight men in the box in an attempt to stifle USC’s running game.The scheme change left Lee and sophomore receiver Nelson Agholor outside with man-to-man coverage, a seemingly favorable position for the Trojans, but they failed to capitalize.“There was a number of explosive plays in the passing game against their corners that we weren’t able to hit which would’ve dramatically changed the outcome of the game,” Kiffin said.Lee let several deep balls slip through his hands and Kessler was off-target on a couple of long attempts to keep the Trojans from blowing the game open.“I missed some throws and we dropped some balls and had some protection issues,” Kessler said. “Obviously, there is some stuff we missed and wished we had back.”A particularly frustrating sequence for the Trojans saw them start three consecutive drives within Utah State’s 35-yard line, golden opportunities for USC to put the game away, only to score three total points.“Obviously we would’ve liked to finish better offensively in the second half,” Kiffin said. “I did feel there was a rhythm early in the first half, and for whatever reason in the second half we weren’t able to establish that. Our defense kept getting us great field position and unfortunately we weren’t able to blow the game out at that point.”DON’T BELIEVE THE HYPEKeeton was largely kept in check despite occasionally flashing the dual-threat skills that had caused some minimal Heisman whispers. The senior finished 21-of-39 for 179 yards and two touchdowns, and was held to -15 rushing yards on 12 attempts.“That’s just all the schemes with [defensive coordinator Clancy] Pendergast. He sets us up every week to play perfect,” redshirt junior defensive end George Uko said. “We had a good plan going the whole week with [defensive line coach Ed Orgeron] for inside tackles to push rush and outside people to align wide and just angle in and rush tight to keep [Keeton] in a tight box.”Utah State had averaged 49.3 points, 550.3 yards and 29 first downs in its first three games, but the Trojans held them to just 14 points, 285 yards and 13 first downs. USC sacked Keeton four times and had 10 tackles for loss on the day.