Ancient hypercarnivores such as dire wolves , cave hyenas , and saber - toothed qat – whose diet consisted of 80 % meat – were up to twice the size of the wolves , spotted hyenas , and lions we have today . And grant to newfangled determination published inProceedings of the National Academy of Sciences , packs of them used to keep even the most humongous of Pleistocene megaherbivores in check . These hunters had a much big impingement on the ecosystem than we conceive : Killing just 17 % of adolescent megaherbivores a twelvemonth would be enough to halt universe growth .
Work with modern - day elephants suggests that huge , hungry industrial plant - eaters like mammoth and giant ground sloths could devastate the vegetation when thickly packed . And while elephants are the largest terrestrial herbivore these days , they ’re smaller , fewer , and less widely distribute than some of those prehistoric giants . So how did those ancient landscape painting hold up this demolition ?
“ Based on reflexion of living megaherbivores , such as elephants , rhino , giraffes and hippos , scientist have generally thought that these species were largely immune to depredation , mainly because of their turgid size of it as adults and strong maternal aegis of very young offspring,”UCLA ’s Blaire Van Valkenburghsays in astatement . Yet in Botswana ’s Chobe National Park , for instance , 74 elephants were killed by lions over a four - class period . The majority of the kills were juveniles and sub - grownup ( nine year or untested ) , and they were typically reach by groups of marauder working together . Sometimes one king of beasts would leap on and burn the back of the victim , while the others lop its himblimb muscles .
If they worked together , saber - toothed cats ( Smilodon ) may have been capable of take down juveniles of the Pleistocene ’s large herbivore . Mauricio Anton
To study the wallop of hypercarnivores in the Pleistocene , which ended about 11,700 years ago , Van Valkenburgh and colleagues developed a series of theoretical account for estimating the size range of both predatory animal and their prey . For predators , they turn to fossilized first molars . “ In the fossil disk , the one affair we ’ve suffer a lot of is teeth,”Van Valkenburgh supply . To infer herbivore size , the squad developed formulas for the relationship of shoulder acme to body mass using data on mod elephants . They also analyze kills in the wild to judge typical and maximum quarry sizes hunt by single piranha and those in groups .
Juvenile megaherbivores , they conclude , would have been susceptible to predation – specially if the carnivores were organize into groups and the young herbivores were just get down to venture out a bit to scrounge for themselves . A single Pleistocene qat could have shoot down a 2- to 4 - year old mammoth , for example . And in a grouping , extinct lion and saber - toothed cats could have killed adult female mammoth weigh up to 6,700 kg ( 14,770 British pound sterling ) .
“ We contribute together a various array of data ( fossil , historical , recent behavioural , new consistence mass estimates ) to seek to predict the typical and maximum fair game sizing of the large Pleistocene carnivore , ” Van Valkenburgh separate IFLScience . “ And we brought up the idea that group ( pridefulness , kin , pack ) sizes were plausibly larger in the Pleistocene – devote that they were significantly big just 60 old age ago – and this would have made killing juveniles and sub - full-grown megaherbivores even easier for these magnanimous cats and hyena . ” Human hunting in the last century selected against large groups , since they were easier to detect .
