在童話中，拉動(dòng)圣誕老人雪橇領(lǐng)頭的一只圣誕馴鹿名叫魯?shù)婪?，它擁有一個(gè)獨(dú)一無二的紅鼻子,，能像燈塔一樣穿透迷霧更好的為圣誕老人領(lǐng)路。而現(xiàn)實(shí)中科學(xué)家們也發(fā)現(xiàn)馴鹿的一個(gè)特殊本領(lǐng),，它們能夠看到紫外線以幫助自己更好的生存,。
據(jù)國(guó)外媒體報(bào)道，研究者們發(fā)現(xiàn),，馴鹿能夠看到大多數(shù)動(dòng)物都看不到的太陽紫外線,，這項(xiàng)本領(lǐng)能夠有助它們?cè)诒煅┑氐臉O地環(huán)境中更好的生存。據(jù)了解,，科學(xué)家們認(rèn)為這種特殊視力能夠讓馴鹿及時(shí)發(fā)現(xiàn)隱藏的肉食動(dòng)物,，比如狼，從而提高生存幾率,。
領(lǐng)導(dǎo)此項(xiàng)研究的是倫敦大學(xué)的格倫-杰弗瑞(Glen Jeffery)教授,，他說：“我們發(fā)現(xiàn)馴鹿不僅可以看到紫外線，而且能夠利用這種本領(lǐng)來尋找食物和發(fā)現(xiàn)危險(xiǎn),。”幾乎所有的人類和其它哺乳動(dòng)物根本無法看到紫外線,，人類的眼睛角膜和水晶體會(huì)吸收紫外線阻止其接觸到視網(wǎng)膜，而這樣會(huì)導(dǎo)致角膜和水晶體損壞,，導(dǎo)致雪盲癥的發(fā)生,。
人們能夠看到的波長(zhǎng)大約為400~700nm，而紫外線是電磁波譜中波長(zhǎng)從10nm到400nm輻射的總稱,，不能引起人們的視覺,。杰弗瑞教授的研究小組實(shí)驗(yàn)結(jié)果表明，馴鹿能夠看到320~350nm的波長(zhǎng),。除了能夠減少紫外線傷害避免雪盲癥的發(fā)生之外,，并且在白茫茫的雪地中，動(dòng)物的尿液和毛皮都能夠吸收紫外線,，這樣一來馴鹿就能夠比較容易發(fā)現(xiàn)捕食者的存在,。據(jù)了解,，該項(xiàng)研究的結(jié)果已發(fā)表在《實(shí)驗(yàn)生物學(xué)期刊》(Journal of Experimental Biology)中。（生物谷Bioon.com）
生物谷推薦原文出處：
The Journal of Experimental Biology DOI: 10.1242/?jeb.053553
Arctic reindeer extend their visual range into the ultraviolet
Christopher Hogg, Magella Neveu, Karl-Arne Stokkan, Lars Folkow, Phillippa Cottrill, Ronald Douglas, David M. Hunt and Glen Jeffery
The Arctic has extreme seasonal changes in light levels and is proportionally UV-rich because of scattering of the shorter wavelengths and their reflection from snow and ice. Here we show that the cornea and lens in Arctic reindeer do not block all UV and that the retina responds electrophysiologically to these wavelengths. Both rod and cone photoreceptors respond to UV at low-intensity stimulation. Retinal RNA extraction and in vitro opsin expression show that the response to UV is not mediated by a specific UV photoreceptor mechanism. Reindeer thus extend their visual range into the short wavelengths characteristic of the winter environment and periods of extended twilight present in spring and autumn. A specific advantage of this short-wavelength vision is the use of potential information caused by differential UV reflections known to occur in both Arctic vegetation and different types of snow. UV is normally highly damaging to the retina, resulting in photoreceptor degeneration. Because such damage appears not to occur in these animals, they may have evolved retinal mechanisms protecting against extreme UV exposure present in the daylight found in the snow-covered late winter environment.
