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Chapter 33 Nature's Wonderful Nature (3)
Scientists set up an avian casino in which pigeons could place their bets on one of two symbols. Peck at symbol 1 and you get three food pellets. Never more, never less. Symbol 2 was the wildcard. Choose that one and 20 percent of the time, you'll hit the jackpot: 10 food pellets. The rest of the time you'll get nothing. But the lure of the big win was too hard to resist: pigeons chose to gamble more than 80 percent of the time, even though, on average, that path paid out fewer pellets.
Perhaps it's the joy of a pleasant surprise. Because even for a literal bird brain, hitting the lottery is a hoot.
Vocabulary
Blackjack ["bl? kd?? k] n. Blackjack of poker;
vt. to beat with a stick

gamble ["ɡ?mbl] vi. Gambling, speculation;
vt. Gambling, desperate;
n. adventure, gambling

Critters ["krit?] n. creatures, small animals (plural form of critter)
casino [k? "si: n? u] n. casino, club, casino
pellets ["pelits] pellets, small balls (plural of pellets);

v. Make into a small ball (third-person singular of pellet)
Practice
What do you think of pigeons' action?

Translation
Blackjack, slot machines and Texas hold'em – people love to gamble, but it's not just people.Pigeons also give up some immediate benefits for greater rewards, research shows.

Foraging theory tells us that animals will implement the so-called "a bird in the hand is better than two in the bush" proverb, and they are even more steadfast when it comes to food.Eating is key to survival, so smart animals don't take unnecessary risks.But new research suggests that pigeons don't always play it safe.

Scientists have set up an aerial casino that lets pigeons "bet" between two signs.At mark 1, the pigeon can peck three grains of food, just three, no more and no less.Mark 2 is uncharted territory.If this place is chosen, the pigeon has a 20% chance of winning the first prize: ten grains of food.The other 80% of the time you won't get anything.But the first prize is too much to resist: 80% of the time the pigeons will take the gamble, even though this option results in less food on average.

Maybe it's a pleasant surprise.For even in the unimaginative mind of a bird, gambling is a tempting crime.

Exercise
What do you think of the risk-taking behavior of pigeons?

05 Why a Cat Purrs Why a Cat Purrs
No one knows for sure why a domestic cat purrs, but many people interpret the sound as one of contentment. Our understanding of why a domestic cat purrs is becoming more complete; most scientists agree that the larynx (voice box), laryngeal muscles, and a neural oscillator are involved.
Kittens learn how to purr when they are a couple of days old. Vets suggest that this purring tells “Mom” that “I am okay” and that “I am here”. It also indicates a bonding mechanism between kitten and mother.
As the kitten grows into adulthood, purring continues. Many suggest a cat purrs from contentment and pleasure. But a cat also purrs when it is injured and in pain. Dr. Elizabeth Von Muggenthaler, a famous biologist, has suggested that the purr, with Its low frequency vibrations, is a “natural healing mechanism”. Purring may be linked to the strengthening and repairing of bones, relief of pain, and wound healing.
Purring is a unique vocal feature in the domestic cat. However, other species in the Felidae family also purr: bobcat, cheetah, Eurasian lynx, puma, and wild cat. Although some big cats like lions exhibit a purr-like sound, studies show that the Patherinae subfamily: lion, tiger, leopard, jaguar, snow leopard, and clouded leopard do not exhibit true purring.
What makes the purr distinctive from other cat vocalizations is that it is produced during the entire respiratory cycle (inhaling and exhaling). Other vocalizations such as the “meow” are limited to the expiration of the breath.
Vocabulary
domestic [d? u"mestik] adj. Domestic, domestic, domesticated;
n. servant, domestic product

Oscillator ["? sileit?] n. [Electronic] oscillator, swinging animal, shaking person
mechanism ["mek?niz?m] n. mechanical device, technique, principle, way, process

Vibration [vai"brei??n] n. vibration, hesitation, telepathy
mechanism ["mek?niz?m] n. mechanism, principle, way, process

respiratory ["resp? r? t? ri, ri" spai? -] adj. breathing

Vocalizations ["v?uk?laizei??ns, -li"z-] n. Vocalization, pronunciation, vocalization method

Practice
Write yes if the sentence is true. Write no if the sentence is not true.
1. Cats' purrs are concerned with the larynx, laryngeal muscles, and a neural oscillator.
2. Kittens' purrs indicate a bonding mechanism between them and mother.

3. Cat maybe purrs when it is injured and in pain.

4. Purring is a unique vocal feature in the cat.

5. Lion do not exhibit true purring.

Translation
No one knows exactly why house cats purr, but many people interpret the sound as a sign of contentment.Our understanding of why domestic cats purr is improving, and most scientists agree that the phenomenon has something to do with the larynx, throat muscles, and neuronal oscillators.

Kittens learn to purr when they are a few days old.Veterinarians think this is telling the mother cat something like "I'm fine" and "I'm here."Purring also shows that there is an intimate psychopathic relationship between the kitten and its mother.

Kittens will continue to purr as they grow into adults.Many people assume that cats make this noise out of contentment and pleasure.However, cats can also purr when they are injured or in pain.The famous biologist Elisabeth von Mugenthaler proposed that the purr, with its low-frequency vibrations, is a "natural healing mechanism".Purring may be linked to strengthening and straightening bones, relieving pain, and healing wounds.

Purring is a unique pronunciation characteristic of domestic cats.However, within the cat family, other species also purr, such as the bobcat, cheetah, Eurasian lynx, cougar, and feral cat.Although big cats such as lions also purr-like, studies have shown that members of the leopard subfamily, such as lions, tigers, jaguars, jaguars, snow leopards and clouded leopards, do not purr.

Purring differs from other feline vocalizations in that the former is produced during the entire breathing cycle, including inhalation and exhalation, whereas other vocalizations like "meow" are produced only during exhalation.

Exercise
True or false:

1.Purring in cats is associated with the larynx, laryngeal muscles, and neuronal oscillators.

2.The purring of the kitten shows that there is an intimate psychosensory relationship between the kitten and its mother cat.

3.Cats may purr when they are injured or in pain.

4.Only cats purr.

5.Lions cannot purr properly.

1．yes　2．yes　3．yes　4．no　5．yes
06 Bees Help Track Criminals Bees help catch criminals
Unless you're talking about killer bees, it's hard to imagine a situation in which “killers” and “bees” would be related. But it turns out that scientists are using the same mathematical model to describe the behavior of both bumblebees and human serial killers.
The method, called geographic profiling, was developed by a detective who was trying to predict where serial killers might live based on where they commit their crimes. Believe it or not, murderers operate fairly close to home. But not too close. They maintain a kind of kill-free “buffer zone” around their actual digs.
A similar pattern of activity seems to hold true for bumblebees—when they're foraging for food. Bees tend to avoid stopping at flowers too close to home, perhaps to reduce the risk of drawing predators, parasites or nosy scientists to the nest. working with the former detective, scientists in the UK found that geographic profiling allowed them to locate the entrance to a hive based on mapping which flowers the bees visit. Repeating such experiments, with bees or other foraging critters, could help hone the model for catching criminals.
Vocabulary
bumblebees ["b? mblbi:] n. [Kun] bumblebee

serial ["si? ri? l, "si: r-] adj. Continuous, serial, installment repayment;
n. serial novel, periodical

predict [pri"dikt] vt. forecast, predict;
vi. to make a prediction
crimes crime [kraim] plural form) n. crime
Predators ["pred? t?] n. [action] predator; [action] carnivore, predator

geographic [d? i? "gr? fik] adj. geographical, geographical
Practice
Why can the bees help track criminals?

Translation
Unless you're talking about deadly bees, it's hard to imagine linking "killer" with "bee."But scientists can use the same mathematical models to describe the behavior of bumblebees and serial killers.

The method, called "geographic profiling," was developed by a detective trying to predict where a serial killer lived based on where the offender committed the crime.Believe it or not, the place where the murderer committed the murder was actually not far from his residence, but not very close either.They maintain a certain crime scene-free "buffer zone" near their lair.

A similar scenario occurs when the bumblebee forages.Bees tend not to linger on flowers that are close to home, perhaps to avoid attracting other predators, parasites or "nosy" scientists to their hives.British scientists teamed up with the aforementioned detectives and found that geographic portraits of the different flowers the bees had plucked could help them find the hive's entrance.Repeating such experiments with bees or other animals might further improve the model's accuracy and help catch criminals.

Exercise
Why bees help catch criminals

The bumblebees and human serial killers have similar pattern of behavior.

07 Are Cats as Detestable as Rats Are Cats as Detestable as Rats?
(End of this chapter)