Unit Two Text (点击收听全文) Is there anything we can learn from deer? During
the "energy erisis" of 1973 -- 1974 the writer of this
essay was living in northern Minnesnta and was able to
observe how deer survive when winter arrives. The lessons
he learns about the way deer conserve energy turn out
applicable to our everyday life.
DEER AND THE El'VERGY CYCLE Aaron N. Moen
Some persons say that love makes the world go round. Others of a less
romantic and more practical turn of mind say that it isn't love; it's money.
But the truth is that it is energy that makes the world go round. Energy is
the currency of the ecological systern and life becomes possible only when
5 food is converted into energy, which in turn is used to seek more food to
grow, to reproduce and to survive: On tliis cycle all life depends.
It is fairly well known that wild animals survive from year to year by
eating as much as they can during times of plenty, the summer and fall,
storing the excess, usually in the forrn of fat, and then using these
10 reserves of fat to survive during the hard times in winter when food is
scarce. But, it is probably less well known that even with their stored fat,
wild anirnals spend less energy to live in winter than in summer.
A good case in point is the white--tailed deer. Like most wildlife, deer
reproduce, grow, and store fat in the summer and fall when there is plenty
15 of nutritious food available. A physically mature female deer in good condi-
tion who has conceived in November and given birth to two fawns during the
end of May or first part of June, must search for food for the necessary
energy not only to meet her body's needs but also to produce milk for her
fawns. The best milk production occurs at the same time that new plant
20 growth is available. This is good timing, because milk production is an
energy consuming process -- it requires a lot of food. The cost can not be
met unless the region has ample food resources.
As the summer progresses and the fawns grow, they become less dependent
on their mother's milk and more dependent on growing plants as food
25 sources. The adult males spend the summer growing antlers and getting fat.
Both males and females continue to eat high quality food in the fall in
order to deposit body fat for the twinter. In the case of does and fawns, a
great deal of energy is expended either in milk production or in growing,
and fat is not accumulated as quickiy as it is in full grown males. Fat re-
30 serves are like bank accounts to be drawn on in the winter when food sup-
plies are limited and sometimes difficult to reach because of deep snow.
As fall turns into winter, other changes take place. Fawns lose their
spotted coat. Hair on all the deer becomes darker and thicker. The change
in the hair coats is usually complete by September and maximum hair depths
35 are reached by November or December when the weather becomes cold.
But in addition, nature provides a further safeguard to help deer sur-
vive the winter -- an internal physiological response which lowers their
metabolism, or rate of bodily functioning, and hence slows, down their ex-
penditure of energy.The deer become somewhat slow and drowsy.The heart
40 rate drops. Animals that hibernate practice energy conservation to a
greater extreme than deer do. Although deer don't hibernate, they do the
same thing with their seasonal rhythms in metabolism. Deer spend more en-
ergy and store fat in the summer and fall when food is abundant; and spend
less energy and use stored fat in the winter when food is less available.
45 When the "energy crisis" first came in 1973 - 1974, I was living with
my family in a cabin on the edge of an area where deer spend the winter in
northern Minnesota, observing the deer as their behavior changed from more
activity in summer and fall to less as winter progressed, followed by an
increase again in the spring as the snow melted. It was interesting and
50 rather amusing to listen to the advice given on the radio: "Drive only when
necessary, " we were told. " Put on more clothes to stay warm, and tum the
thermostat on your furnace down. " Meanwhile we watched the deer reduce
their activity, grow a winter coat of hair, and reduce their metabolism as
they have for thousands of years. It is biologically reasonable for deer to
55 reduce their cost of living to incresse their chances of surviving in
winter.
Not every winter is critical for deer of course. If the winter has
light snow, survival and productivity next spring will be high. But if deep
snows come and the weather remains cold for several weeks, then the deer
60 must spend more energy to move about, food will be harder to find,and they
must then depend more on their fat reserves to pull them through. If such
conditions go on for too long some will die, and only the largest and
strongest are likely to survive. That is a fundamental rule of life for
wild, free wandering animals such as deer.
65 Yes, life -- and death, too - is a cycle that goes round and round, and
when animals die their bodies become food for other life forms to use by
converting them into energy.
And the cycle continues.
New Words (点击收听单词) deer /n. (sing. or pl. ) 鹿
romantic/ a. belonging to or suggesting romance;fanciful, not practical
浪漫的; 幻想的
turn n. a natural tendency; inclination (天生)倾向
currency /n. money that is actually in use in a country 通货，货币
ecological /a. of or concerning interrelationship of organisms and their
environment 生态的
ecology /n. 生态学
convert /vt. change (from one form, use, etc. into another);cause
(a person)to change his beliefs,etc. 使转变;使改变信仰(等)
excess/ n. the part that is more than enough; the condition of excee-
ding what is usual or necessary 过量; 过渡
reserve/ n. sth. that is being or has been stored for later use 储备(物)
scarce / a. not available in sufficient quantity 缺乏的
wildlife n. animals and plants which live and grow wild
nutritious /a. 有营养的
mature /a. fully grown and developed 成熟的; 成年的
f'emale / a. of the sex that gives birth to young 女(性)的; 雌的
n. a female person, animal or plant
conceive /vt. become pregnant with (young); form (an idea,plan, etc. ) in
the mind 怀(胎) ; 构思
fawn / n. a young deer less than a year old
timing n. selection for maximum effect of the precise moment for be-
ginning or doing sth.时机的选择
consume / vt. eat or drink; use; use up 消耗; 消费
region / n. a place, space or area; a part of the body 地区; (身体的)部位
ample / a. plentiful 充裕的
resource n. (pl.) possessions (esp.of a country), in the form of wealth and
goods, that help one to do what one wants 资源
dependent a. relying (on another) for support
male /meil/a. of the sex that does not give birth to young 男(性)的;雄的
n. a male person, animal or plant
antler / n. the solid,bony horn of a male deer 鹿角,茸角
deposit /vt. put or store for safe keeping; (esp. of a liquid, a river) leave
lying (a layer of matter) 存放;使沉积
doe / n. a fully-grown female deer
expend vt. spend or use up 花费; 耗尽
accumulate / make or become greater in number or quantity; collect or
v. gather 积累; 积聚
account n. a sum of money kept in a bank which may be added to or
taken from 帐户; 存款
spotted a. marked with spots
depth n. the state or degree of being deep 深; 深度, 厚度
safeguard / n. a means of protection against sth. unwanted 预防措施
internal / a. of or in the inside,esp. of the body 内部的;体内的
physiological/ n. 生理的; 生理学的
metabolism / n. 新陈代谢
hence /hens/ ad. therefore 因此, 所以
expenditure / n. expending or using up; the amount of money, time, etc.
expended 花费;用光; 支出额,费用
somewhat ad. by some degree or amount; a little 有点,稍微
drowsy /a. sleepy or half sleepy; making one sleepy 困倦的;催眠的
hibernate /vi. (of some animals) pass the whole of the winter in a state
like sleep 冬眠
extreme /n either end of anything; highest degree 极端
seasonal a. depending on the seasons; changing with the seasons 季节
性的
rhythm /n.. 节奏
abundant / a. more than enough 充足的; 丰富的
cabin / n. a small roughly built, usu. wooden house 小木屋；茅舍
melt /melt/ v. cause(a solid) to become liquid;(of a solid) become liquid
(使)融化; (使)熔化
amusing / a. funny 逗人笑的; 引起乐趣的
amuse vt. cause to laugh or smile
thermostat / n. an automatic device for regulating temperature 恒温器
biologically ad. 生物学上
biological a.
survival n. the fact or likelihood of surviving 幸存
productivity n. the ability or capacity to produce, productiveness 生产力;
生产率; 多产
fundamental / a. basic; most important
Phrases & Expressions
go round f unction smoothly
in the form of 以…形式
in point appropriate ; pertinent 适用的; 相关的
in (good) condition in good health, physically fit
give birth ( to ) bear;(fig.) produce 生(孩子), 产(仔); 产生, 引起
draw on take or use as a source 利用; 动用
slow down (cause to) go more slowly than usual; (cause to) live,work,
etc. in a less active and intense way (使)慢下来; (使)放松
turn down reduce the force, speed, loudness, etc.of (sth.) by using
coritrols 减弱; 关小, 调低
move about travel around; go from one place to another
pull through help (sb.) to survive a period of danger or crisis 使渡过危险
或危机
Proper Name Minnesota / 明尼苏达(美国州名)
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