一項(xiàng)最新研究顯示，現(xiàn)今生存的豹和老虎都是獨(dú)居食肉性動(dòng)物,，但是現(xiàn)已滅絕的劍齒虎很可能是群居動(dòng)物,，它們像現(xiàn)今獅子的生活方式和獵食方法相同。
劍齒虎以其特別長(zhǎng)的犬齒而著名,，這種鋒利的牙齒可達(dá)到7英寸長(zhǎng),，從上頜一直沿伸至下頜。雖然它通常被稱(chēng)為劍齒虎,，但實(shí)際從物種親緣角度上,，它們并不與現(xiàn)今的老虎接近，劍齒虎屬于一種不同的亞科物種,。然而,，它們的體型很大，擁有強(qiáng)壯的肌肉,，體形大小與現(xiàn)今的老虎差不多,。
來(lái)自美國(guó)加州大學(xué)洛杉磯分校和倫敦動(dòng)物學(xué)學(xué)會(huì)的科學(xué)家們推斷劍齒虎是一種群居性動(dòng)物，他們采用了一種獨(dú)特新穎的方法：記錄非洲野生食肉動(dòng)物獵食時(shí)的數(shù)量密度比例,，與北美洲骨骼化石堆中的滅絕食肉物種進(jìn)行對(duì)比分析,。
距今180萬(wàn)至1萬(wàn)年前，劍齒虎生活在北美和南美洲地區(qū),，在美國(guó)洛杉磯拉布雷亞瀝青坑里發(fā)現(xiàn)許多劍齒龍骨骼化石,，依據(jù)一處骨骼化石堆可呈現(xiàn)當(dāng)年食肉動(dòng)物圍獵的一幕：食草動(dòng)物陷入粘性瀝青池中，已奄奄一息,，此時(shí)吸引了許多饑餓的狼和劍齒龍,，但其中一些劍齒虎和狼也陷入瀝青池中喪命。
由于現(xiàn)今的老虎及一些貓科動(dòng)物都是獨(dú)居,，因此科學(xué)家提出遠(yuǎn)古劍齒虎是群居物種的觀點(diǎn)遭到了一些研究人員的置疑,。目前,，這項(xiàng)研究發(fā)表在10月28日出版的《生物學(xué)快報(bào)》上，研究報(bào)告中將拉布雷亞瀝青坑堆積的骨骼化石數(shù)量與非洲的“野外錄音”數(shù)據(jù)進(jìn)行了對(duì)比,。這段“野外錄音”錄制了被獵食動(dòng)物悲傷的叫聲以及獅子和鬣狗的聲音,，重復(fù)播放該段錄音吸引食肉動(dòng)物。通過(guò)這種方法科學(xué)家評(píng)估了非洲東部和南部食肉動(dòng)物的密度,。
重復(fù)播放錄音結(jié)果顯示,，從食肉物種之間群體大小對(duì)比的角度來(lái)講，大型群體食肉動(dòng)物占被錄音吸引動(dòng)物的比例超過(guò)之前的預(yù)想,。事實(shí)上,，大型群體食肉動(dòng)物出現(xiàn)的數(shù)量密度是之前預(yù)想的60倍。當(dāng)這項(xiàng)結(jié)果與拉布雷亞瀝青坑的骨骼化石進(jìn)行對(duì)比,，科學(xué)家發(fā)現(xiàn)劍齒虎的數(shù)量比例符合播放錄音所獲得的大型群體食肉動(dòng)物的比例,。
加州大學(xué)洛杉磯分校生態(tài)學(xué)和進(jìn)化生物學(xué)教授布萊爾·范·瓦爾肯博(Blaire Van Valkenburgh)說(shuō)，“無(wú)論是過(guò)去還是現(xiàn)在的自然界,，這項(xiàng)研究都可以完全解釋群居物種對(duì)于瓜分獵物具有支配優(yōu)勢(shì),。為什么它們?cè)诳赡茉庥鑫ｋU(xiǎn)競(jìng)爭(zhēng)者的狀況下不多幾個(gè)同類(lèi)幫手呢？”
倫敦動(dòng)物學(xué)學(xué)會(huì)資深研究員克莉絲·卡蓬(Chris Carbone)說(shuō),，“現(xiàn)已滅絕的劍齒虎仍有許多未解之謎,，我們幾乎對(duì)它們的生活習(xí)性一無(wú)所知。這項(xiàng)研究讓我們通過(guò)現(xiàn)代食肉動(dòng)物的習(xí)性推斷出滅絕的劍齒虎的特征——它們成群地生活在一起,，以群體方式進(jìn)行捕獵,，而不是隱藏起來(lái)過(guò)著獨(dú)居生活。”（生物谷Bioon.com）
生物谷推薦原始出處：
Biology Letters 10.1098/rsbl.2008.0526
Parallels between playbacks and Pleistocene tar seeps suggest sociality in an extinct sabretooth cat, Smilodon
Chris Carbone1, Tom Maddox1, Paul J. Funston2, Michael G.L. Mills3, Gregory F. Grether4, Blaire Van Valkenburgh4
1 Zoological Society of London, Regent's Park, London NW1 4RY, UK
2 Department of Nature Conservation, Tshwane University of Technology, Private Bag X680, Pretoria 0001, Republic of South Africa
3 The Tony and Lisette Lewis Foundation and Mammal Research Institute, University of Pretoria, Pretoria 0001, Republic of South Africa
4 Department of Ecology and Evolutionary Biology, University of California, 621 Charles E. Young Drive South, Los Angeles, Los Angeles, CA 90095-1606, USA
Inferences concerning the lives of extinct animals are difficult to obtain from the fossil record. Here we present a novel approach to the study of extinct carnivores, using a comparison between fossil records (n=3324) found in Late Pleistocene tar seeps at Rancho La Brea in North America and counts (n=4491) from playback experiments used to estimate carnivore abundance in Africa. Playbacks and tar seep deposits represent competitive, potentially dangerous encounters where multiple predators are lured by dying herbivores. Consequently, in both records predatory mammals and birds far outnumber herbivores. In playbacks, two large social species, lions, Panthera leo, and spotted hyenas, Crocuta crocuta, actively moved towards the sounds of distressed prey and made up 84 per cent of individuals attending. Small social species (jackals) were next most common and solitary species of all sizes were rare. In the La Brea record, two species dominated, the presumably social dire wolf Canis dirus (51%), and the sabretooth cat Smilodon fatalis (33%). As in the playbacks, a smaller social canid, the coyote Canis latrans, was third most common (8%), and known solitary species were rare (<4%). The predominance of Smilodon and other striking similarities between playbacks and the fossil record support the conclusion that Smilodon was social.
