Hippos are vast animals with fearsome tusks and aggressive natures , but they mainly deplete plant . Sometimes they assault people and can tangle withcrocodiles , sure , but they ’re not predators or carnivores . Right ?
But a closer expression reveals that hippos are n’t so herbivorous after all , says biologistJoseph Dudley . Despite their gage - heavy diet and all the adaptations that make them great grazers , hippos have been make love to eat their fair share of meat . There are scatter reports byscientistsandamateur observers(note : NSFW gory picture ) of hippos aggress , bolt down , and eat other animals , stealing putting to death from predator , and scavenging carcasses , including those of other hippos . In anew paperpublished in the journalMammal Review , Dudley and his fellow researchers argue that these incidents are n’t as strange as they seem or isolated to a few brute or population . They say there ’s a pattern of carnivorous behavior in hippo populations across the creature ’s intact range — and that demeanour has consequences for hippos .
Evolution has outfitted hippopotamus and other braggart herbivore for a plant - ground diet , and their guts and the bug that hold out within them are adapt for fermenting and digesting slew of plant material . That does n’t mean these herbivores animals ca n’t add together nitty-gritty to their menu , though . Many can and do . Antelope , cervid , and cattle have been known to fertilise on carrion , birds ’ eggs , birds , little mammalian , and Pisces the Fishes . What might hold most of these animals back from more frequent carnivory , Dudley evoke , is n’t their digestive physiology , but “ biomechanical restriction ” in plug and ingesting meat . In other words , they are n’t built for train down prey or bite into flesh . The hippo is another history .
THOSE WHO CAN, DO
“ Due to its big body size and unusual mouth and dental configurations , the hippo may stand for an extreme case in which the predation and scavenging of large mammals by an ungulated coinage is not cumber by biomechanical factors , ” Dudley and his squad write . Not only can hippos kill and eat other big animals more easy than other herbivore , the researchers say , the fact that they ’re territorial and extremely aggressive may facilitate carnivory , putting them in position where they kill other fauna and can get themselves something to eat .
And eat they do . Since Dudley made the first scientificrecordof carnivory in hippos in 1996 , other cases of hippo carnivory and even cannibalism have also been documented . Dudley lists instance where wild hippos have course on impalas , elephants , kudus , wildebeest , zebra , and other hippos that they either killed themselves or were killed by other predator . Events like these have been seen both during time when carnivory may be a last stamping ground ( e.g. droughts when intellectual nourishment is scarce ) , and when it was merely a convenient chance , like a mass drowning of gnu crossing a river . There are also report of captive river horse in menagerie killing and eating their neighbors , include tapirs , wallabies , flamingoes and Pigmy hippos .
“ Our scientific record , coupled with those of other research worker and observers , demonstrate that the phenomenon of carnivory by hippos is not restricted to special someone or local universe but is an inherent characteristic of the behavioral ecology of hippos , ” the squad writes .
EATING MEAT WHILE WE SLEEP
If that ’s the case , then why did it take so long for anyone to image it out ? Part of the blame can fall on infringe schedule . Hippos are mostly active at Nox , which means their meals , essence or otherwise , unremarkably go unobserved by man . Their carnivorous ways , Dudley thinks , have simply been look out over .
They may also explain why hippos are so susceptible to splenic fever and experience higher mortality rate charge per unit during outbreaks , the research worker say . Hippos , they think , are doubly expose to the disease because they take in and inhale bacterial spores on plants and in the soil like other herbivore , and also consume them when feeding on contaminated carcass . Cannibalism during eruption worsen the problem .
That carnivory might make these outbreaks worse in hippo populations has implications for controlling the disease and protecting both animals and humans . During anthrax irruption among wildlife , many human illnesses come because of contaminated “ bush meat . ” During a 2011 irruption in Zambia , for example , 511 human case of anthrax and at least five death were linked to the great unwashed handling and consuming meat from septic hippos . Burying or cut surmise infected animal carcasses is a standard practice during anthrax irruption , and the research worker think that this may be specially effective in hippo habitats because it takes infected meat off the carte for both humans and hippos .
