如果你以為大象是一只四肢僵硬的大塊頭,，那你可就錯(cuò)了,。
據(jù)美國(guó)《科學(xué)》雜志在線新聞報(bào)道,，當(dāng)研究人員在這種厚皮動(dòng)物的重要關(guān)節(jié)上貼上標(biāo)記物，并用紅外攝像機(jī)記錄它們的運(yùn)動(dòng)過(guò)程時(shí),，他們發(fā)現(xiàn),，大象的關(guān)節(jié)實(shí)際上相當(dāng)靈活；它們四肢的活動(dòng)與馬甚至人類并沒(méi)有大的差別,。這一發(fā)現(xiàn)扭轉(zhuǎn)了科學(xué)家之前的看法,，即大象樹(shù)干一樣的四肢是剛性且笨拙的，它同時(shí)也為研究類似的動(dòng)物——例如恐龍——的運(yùn)動(dòng)提供了重要線索,。研究人員在8月22日的《實(shí)驗(yàn)生物學(xué)雜志》（JEB）網(wǎng)絡(luò)版上報(bào)告了這一研究成果。（生物谷Bioon.com）
生物谷推薦原始出處：
JEB,，doi: 10.1242/jeb.018820,，Lei Ren, John R. Hutchinson
The movements of limb segments and joints during locomotion in African and Asian elephants
Lei Ren1, Melanie Butler1, Charlotte Miller1, Heather Paxton1, Delf Schwerda2, Martin S. Fischer2 and John R. Hutchinson1,*
1 Structure and Motion Laboratory, Department of Veterinary Basic Sciences, The Royal Veterinary College, University of London, Hatfield, Hertfordshire AL9 7TA, UK
2 Institut fuer Spezielle Zoologie und Evolutionsbiologie, mit Phyletischem Museum, Jena 07743, Germany
As the largest extant terrestrial animals, elephants do not trot or gallop but can move smoothly to faster speeds without markedly changing their kinematics, yet with a shift from vaulting to bouncing kinetics. To understand this unusual mechanism, we quantified the forelimb and hindlimb motions of eight Asian elephants (Elephas maximus) and seven African elephants (Loxodonta africana). We used 240 Hz motion analysis (tracking 10 joint markers) to measure the flexion/extension angles and angular velocities of the limb segments and joints for 288 strides across an eightfold range of speeds (0.6–4.9 m s–1) and a sevenfold range of body mass (521–3684 kg). We show that the columnar limb orientation that elephants supposedly exemplify is an oversimplification – few segments or joints are extremely vertical during weight support (especially at faster speeds), and joint flexion during the swing phase is considerable. The `inflexible' ankle is shown to have potentially spring-like motion, unlike the highly flexible wrist, which ironically is more static during support. Elephants use approximately 31–77% of their maximal joint ranges of motion during rapid locomotion, with this fraction increasing distally in the limbs, a trend observed in some other running animals. All angular velocities decrease with increasing size, whereas smaller elephant limbs are not markedly more flexed than adults. We find no major quantitative differences between African and Asian elephant locomotion but show that elephant limb motions are more similar to those of smaller animals, including humans and horses, than commonly recognized. Such similarities have been obscured by the reliance on the term `columnar' to differentiate elephant limb posture from that of other animals. Our database will be helpful for identifying elephants with unusual limb movements, facilitating early recognition of musculoskeletal pathology.
