In spring, the young, delicate shoots in the forest light up, bright and May green. The buds and shoots are the future of the forests as they allow young trees to grow. The problem for the trees is: Roe1 deer like to eat them, and especially their buds. With a bit of luck, the young, gnawed2 saplings will only take a few more years to grow than their non-bitten conspecifics. In the worst case, they will become stunted3 trees, or they will have to give up their fight for survival after a number of years. In this respect, roe deer can cause a great deal of damage and hinder the regeneration of many deciduous4 tree species. In order to protect themselves against roe deer browsing5, trees purposely put up a fight. By studying young beeches6 (Fagus sylvatica) and maples7 (Acer pseudoplatanus), biologists from the Leipzig University and the German Centre for Integrative Biodiversity Research (iDiv) have now found out that trees are able to recognise precisely8 whether a branch or bud has been purposefully nibbled9 off by a roe deer — or just randomly10 torn off by a storm or other mechanical disturbance11. The saliva12 of the animals gives them the signal. If a deer feeds on a tree and leaves its saliva behind, the tree will increase its production of salicylic acid. This hormone13, in turn, signals to the plant to increase the production of specific tannins. It is known for some of these substances that they influence the feeding behaviour of roe deer, with the result that the deer lose their appetite for the shoots and buds. In addition, the saplings increase their concentrations of other plant hormones14, growth hormones in particular. These hormones enhance the growth of the remaining buds to compensate15 for the lost ones.

“On the other hand, if a leaf or a bud snaps off without a roe deer being involved, the tree stimulates16 neither its production of the salicylic acid signal hormone nor the tannic substances. Instead, it predominantly produces wound hormones,” explains Bettina Ohse, lead author of the study. The scientists reached their conclusions by outsmarting the saplings: They simulated a roe deer feeding on them by cutting off buds or leaves and trickling17 real roe deer saliva on the cut surface from a pipette. Shortly after, they recorded the concentrations of the hormones and tannins in the saplings.

“Following this initial fundamental research, it would now be interesting to also examine other tree species and their defence strategies against roe deer”, says Ohse. “If some turn out to be better defended, these species could possibly be used more in forests in the future.”

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1 roe LCBzp
n.鱼卵；獐鹿
参考例句：
We will serve smoked cod’s roe at the dinner.宴会上我们将上一道熏鳕鱼子。
I’ll scramble some eggs with roe?我用鱼籽炒几个鸡蛋好吗？
2 gnawed 85643b5b73cc74a08138f4534f41cef1
咬( gnaw的过去式和过去分词 )； （长时间） 折磨某人； （使）苦恼； （长时间）危害某事物
参考例句：
His attitude towards her gnawed away at her confidence. 他对她的态度一直在削弱她的自尊心。
The root of this dead tree has been gnawed away by ants. 这棵死树根被蚂蚁唼了。
3 stunted b003954ac4af7c46302b37ae1dfa0391
adj.矮小的；发育迟缓的
参考例句：
the stunted lives of children deprived of education 未受教育的孩子所过的局限生活
But the landed oligarchy had stunted the country’s democratic development for generations. 但是好几代以来土地寡头的统治阻碍了这个国家民主的发展。
4 deciduous 992yy
adj.非永久的；短暂的；脱落的；落叶的
参考例句：
Overgrown deciduous shrubs can be cut back at this time of year.过于繁茂的落叶灌木可以在每年的这个时候修剪。
Deciduous trees shed their leaves in autumn.落叶树木在秋天落叶。
5 browsing 509387f2f01ecf46843ec18c927f7822
v.吃草( browse的现在分词 )；随意翻阅；（在商店里）随便看看；（在计算机上）浏览信息
参考例句：
He sits browsing over[through] a book. 他坐着翻阅书籍。 来自《简明英汉词典》
Cattle is browsing in the field. 牛正在田里吃草。 来自《简明英汉词典》
6 beeches 7e2b71bc19a0de701aebe6f40b036385
n.山毛榉( beech的名词复数 )；山毛榉木材
参考例句：
The beeches, oaks and chestnuts all belong to the same family. 山毛榉树、橡树和栗子树属于同科树种。 来自互联网
There are many beeches in this wood. 这片树林里有许多山毛榉。 来自互联网
7 maples 309f7112d863cd40b5d12477d036621a
槭树，枫树( maple的名词复数 )； 槭木
参考例句：
There are many maples in the park. 公园里有好多枫树。
The wind of the autumn colour the maples carmine . 秋风给枫林涂抹胭红。
8 precisely zlWzUb
adv.恰好，正好，精确地，细致地
参考例句：
It’s precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
The man adjusted very precisely.那个人调得很准。
9 nibbled e053ad3f854d401d3fe8e7fa82dc3325
v.啃，一点一点地咬（吃）( nibble的过去式和过去分词 )；啃出（洞），一点一点咬出（洞）；慢慢减少；小口咬
参考例句：
She nibbled daintily at her cake. 她优雅地一点一点地吃着自己的蛋糕。 来自《简明英汉词典》
Several companies have nibbled at our offer. 若干公司表示对我们的出价有兴趣。 来自《简明英汉词典》
10 randomly cktzBM
adv.随便地，未加计划地
参考例句：
Within the hot gas chamber, molecules are moving randomly in all directions. 在灼热的气体燃烧室内，分子在各个方向上作无规运动。 来自辞典例句
Transformed cells are loosely attached, rounded and randomly oriented. 转化细胞则不大贴壁、圆缩并呈杂乱分布。 来自辞典例句
11 disturbance BsNxk
n.动乱，骚动；打扰，干扰；(身心)失调
参考例句：
He is suffering an emotional disturbance.他的情绪受到了困扰。
You can work in here without any disturbance.在这儿你可不受任何干扰地工作。
12 saliva 6Cdz0
n.唾液，口水
参考例句：
He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
Saliva dribbled from the baby’s mouth.唾液从婴儿的嘴里流了出来。
13 hormone uyky3
n.荷尔蒙，激素，内分泌
参考例句：
Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
14 hormones hormones
n. 荷尔蒙，激素 名词hormone的复数形式
参考例句：
This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
The adrenals produce a large per cent of a man’s sex hormones. 肾上腺分泌人体的大部分性激素。
15 compensate AXky7
vt.补偿，赔偿；酬报 vi.弥补；补偿；抵消
参考例句：
She used her good looks to compensate her lack of intelligence. 她利用她漂亮的外表来弥补智力的不足。
Nothing can compensate for the loss of one’s health. 一个人失去了键康是不可弥补的。
16 stimulates 7384b1562fa5973e17b0984305c09f3e
v.刺激( stimulate的第三人称单数 )；激励；使兴奋；起兴奋作用，起刺激作用，起促进作用
参考例句：
Exercise stimulates the body. 运动促进身体健康。 来自《简明英汉词典》
Alcohol stimulates the action of the heart. 酒刺激心脏的活动。 来自《现代英汉综合大词典》
17 trickling 24aeffc8684b1cc6b8fa417e730cc8dc
n.油画底色含油太多而成泡沫状突起v.滴( trickle的现在分词 )；淌；使)慢慢走；缓慢移动
参考例句：
Tears were trickling down her cheeks. 眼泪顺着她的面颊流了下来。
The engine was trickling oil. 发动机在滴油。 来自《简明英汉词典》

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