News on Animals

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News on Animals
By Cathy Chang
Snakes
Starting Questions
◊ What are the characteristics of snakes?
◊ Do you see them as essential to the
environment or just dangerous reptiles?
◊ How is the image of snakes usually
used in places like books, movies, etc.?
“Snake-Fang Evolution Mystery
Solved -- ‘Major Surprise’”
The diverse and deadly array of venomous snakes living today all arose
from a single fanged ancestor, a new study suggests.
Vipers, cobras, and other snakes that have fangs at the fronts of their jaws
surprisingly begin life like snakes that have poisonous fangs at the back
of their jaws, said a team led by Freek Vonk of Leiden University in the
Netherlands.
The discovery suggests venomous fangs--the lethal evolutionary invention
that led to snakes becoming so successful--arose only once about 60
million years ago.
The origins of venom-injecting snakes have long been the source of
scientific controversy, because the contrasting fang positions of diverse
snake groups pointed to independent evolution.
But a study of the embryos of eight front- and rear-fanged species has
found that fangs always first appear at the back of the upper jaw before
migrating forward in vipers and cobras.
This previously unidentified transformation in the unborn young occurs due
to "rapid growth of some parts of the upper jaw relative to the others,"
Vonk explained.
(Source)
Vocabulary
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Diverse 多種多樣的;多變化的
Array 一系列;大量
Venomous 分泌毒液的
Fanged 有尖牙的
Vipers 奎蛇
Cobras 眼鏡蛇
Jaws 頜;顎;下頜,下巴
Poisonous 有毒的
Lethal 致命的
Evolutionary 進化的
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Invention 發明,創造
Origins 起源;由來
Venom-injecting 注射毒液
Contrasting 形成鮮明對比的
Independent 獨立的
Embryos 胚胎
Migrating 遷移;移居
Transformation 變化;轉變
Relative to 成比例
Lemurs
Starting Questions
◊ Have you ever seen real lemurs?
◊ What are some characteristics of lemurs?
◊ What is your reaction when you see
these mammals?
“‘Cross Dressing’ Lemurs Appear
Male to Avoid Conflict”
Young female red-fronted lemurs in Madagascar adopt male
coloration to dupe their aggressive female group-mates, a new
study found.
These "cross dressing" primates thus avoid the wrath of older
females, which would attack them to reduce sexual competition.
All red-fronted lemurs are born with the same grayish brown fur and
rusty-red crowns that distinguish adult males.
At 7 to 17 weeks later, females' coats change to a cinnamon hue,
and their crowns become white.
"We knew from our longer-term observations that there was a lot of
female aggression in red-fronted lemurs," said study author
Claudia Fichtel of the University of Göttingen's German Primate
Center.
"Females compete fiercely over limited breeding opportunities, and
we wanted to know if hiding femininity was a way to avoid being
attacked," Fitchtel said.
(Source)
Vocabulary
◊ Madagascar 馬達加斯
加
◊ Adopt 採取
◊ Coloration 天然色
◊ Dupe 欺騙
◊ Aggressive 好鬥的,挑釁
的
◊ Mates 同伴
◊ Primates 靈長類
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Wrath 憤怒,狂怒
Crowns 頭頂;頭
Coats 皮毛
Cinnamon 淺紅褐色
Hue 色調,色澤
Breeding 生育,生殖
Femininity 女子氣質
Bees
Starting Questions
◊ What are the characteristics of bees?
◊ What are the advantages of having
bees in our environment?
Disadvantages?
◊ Have you ever been stung by a bee?
“Bees Enlisted to Attack
Crows in Tokyo”
After years of being attacked by crows, a colony of seabirds nesting in
Tokyo is getting an unlikely ally: the tiny honeybee.
Conservationists hope bees will repel the crows, based on the insects'
tendency to attack anything dark-colored that approaches their
hives.
This year beehives from rural areas were relocated to the top of a
large water-treatment facility near Tokyo's international airport,
where as many as 4,000 birds known as little terns nest after a long
migration from Australia, New Zealand, and Papua New Guinea.
Although they are not endangered internationally, little terns are listed
as "vulnerable" in Japan's Red Data Book of threatened species.
That's because the terns' nesting sites in the country are being
destroyed by construction work and other human activities, so the
birds are considered potentially at risk in the future.
The terns near the airport have long been victims of Tokyo's crows.
(Source)
Vocabulary
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Crows 烏鴉
Colony 集群;群體
Seabirds 海鳥
Nesting 巢;窩;穴
Ally 伙伴,助手
Conservationists 天然資源
保護論者
◊ Repel 擊退;驅除
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Tendency 傾向
Hives 蜂房;蜂巢
Rural 鄉下
Relocated 重新安置
Terns 燕鷗
Endangered 快要絕種的
Potentially 潛在地;可能地
Chameleons
Starting Questions
◊ What are some of the characteristics of
chameleons?
◊ Why do some people like to raise them
as pets?
“Record-Breaking Chameleons
Live Only a Few Months”
Members of a rare chameleon species all hatch in the same month,
then die only four to five months later--making them the
shortest-lived four-limbed vertebrates, a new study says.
Labord's chameleon had been identified in 1872 in the arid
southwest of the island of Madagascar off the east coast of
Africa. But it wasn't until 2003 that a zoologist noticed there was
something strange about this particular species.
"It was just bizarre, because I could find only adults and no
juveniles whatsoever," said study co-author Kristopher Karsten
of Oklahoma State University.
"So I thought, Well, either my eye isn't trained very well to find
these juveniles, or they're not there. And if they're not there,
maybe that means that every one is the same age and they're
an annual species.
"After studying the chameleons for three more seasons, Karsten
and his colleagues were certain that the entire population of
Labord's chameleon (Furcifer labordi) turns over every year.
(Source)
Vocabulary
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Rare 稀有的,罕見的
Chameleon 變色龍
Hatch 孵出
Limb 肢;臂;腳;翼
Vertebrates 脊椎動物
Arid 乾旱的;乾燥的
Zoologist 動物學家
◊ Particular 特殊的;特定
的
◊ Species 種類
◊ Bizarre 異乎尋常的
◊ Juveniles 少年的
◊ Annual 一年一次的
◊ Turns over 更換
Birds
Starting Questions
◊ What are some characteristics of birds?
◊ What species of birds can you name?
◊ Do they make good pets?
“Migrating Birds Understand
‘Foreign Languages’”
Like avid travelers picking up local languages, migrating birds appear to
learn and understand the common calls of unrelated bird species
that they encounter during their long journeys, new research reveals.
Birds that remain in one location throughout the year have no difficulty
identifying predators, such as hawks, ferrets, and snakes.
Migrators, however, constantly face the threat of encountering predators
in their travels that they do not immediately recognize as dangerous.
Some ecologists had previously suggested that long-distance travelers
pick up cues from local species to obtain information on unfamiliar
predators, but evidence for this theory has been thin.
To explore the possibility, researchers at Queen's University in Ontario,
Canada, played predator warning calls made by both local and
foreign species to birds passing through Belize on long migrations as
well as to local birds and monitored their reactions.
(Source)
Vocabulary
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Avid 勁頭十足的
Common 普通的;常見的
Encounter 遇到
Predators 掠奪者
Ferrets 雪貂,白鼬
Ecologists 生態學者
Cues 暗示,信號;線索
◊ Local 地方性的;當地的,
本地的
◊ Obtain 得到,獲得
◊ Unfamiliar 不熟悉的;不
常見的
◊ Evidence 證據
◊ Theory 理論;原理
◊ Monitor 監視
◊ Reactions 反應
Reference
“Animal News.” National Geographic. 1
Aug 2008.
<http://news.nationalgeographic.
com/news/animals_05.html>.
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