自然英语

A rakish, eye-catching crest really sets some birds apart. Picture the Blue Jaysof the East… or Stetter’s Jays of the West.

Ajay’s crest is made up of a slender array of feathers on top of its head. Thesefeathers are a bit longer and can be spiked up or slicked back, depending onwhat the bird is trying to communicate.

Whenjays are sitting on eggs, feeding their young, or hanging out with their mate,their crests lie low. But in the case of heightened arousal, like in courtshipor conflict, a jay’s sharply raised crest tells a tale.

Thesame goes for Northern Cardinals and, perhaps, most crested birds. Even birdswithout crests, like crows or sparrows, sometimes puff up their short crownfeathers.

Whysome species have crests and others don’t remains a complex evolutionaryquestion dating back to the dinosaurs.

Birdslay eggs. That means they don’t nurse their young… right? Well, have you everheard of something called “pigeon milk?”

Pigeons,one of the most ancient of domesticated birds, feed their nestlings a peculiar,milky liquid- straight from the adult’s beak to the baby’s throat.

It’soften called “crop milk,” because it comes from special cells in the birds’crop. The crop is a section of the lower esophagus in some birds that is usedfor storing food before digestion.

Unlikemilk from mammals, pigeon milk doesn’t come from a mammary gland. But it doescome loaded with antioxidants and immune boosters that help the new hatchlingssurvive.

Acouple of days before their eggs hatch, both pigeon parents start making themilky substance, which they’ll feed their hatchlings over the first ten days oftheir lives. When the special feeding stops, the special crop milk cells returnto normal.

Pigeonsand doves aren’t the only birds that can make this special milk. Flamingos andsome species of penguins can, too.

Hello welcome to wild Suzhou, today I’ll be talking about theblue-spotted ribbon-tail ray

Blue spotted ribbon-tail rays live near the seafloor in coral reefs and inhabit temperate waters. It is able to dig in sand to conceal itself, andit uses this skill to catch prey. Another way it finds food is scooping up thesand into its mouth and filtering out the food. Its diet consists of small seaanimals like sand worms, shrimp, hermit crabs, small fish, and mussels.

 The population of the rays issuffering though due to fishing and habitat loss, like coral reefsdeteriorating. They are also traded as pets or to go to aquariums. Some of theblue spotted ribbon-tail rays predators include hammerhead sharks, orcas, andhuman activity. This ray is quite venomous, and capable of killing a human.Most of the time, these rays live on their own, except when migrating orraising offspring. It is gray, with bright blue spots covering its body, and atthe end of its tails are its stingers.

    For wild Suzhou I’mPalm-tree and thanks for listening.

Thisrollicking song belongs to a Black-headed Grosbeak. Like most birds, the malegrosbeak begins singing in earnest a few days after reaching his traditionalnesting grounds in spring.

And,like most birds, he sings frequently when trying to attract a mate. He’ll singa bit less while he and his mate incubate eggs, but pick up the pace againafter the young hatch. By late summer, his singing will cease.

Everwonder how much a bird sings in one day? Some patient observers have shown thata typical songbird belts out its song between 1,000 and 2,500 times per day.Even though most bird songs last only a few seconds, that’s a lot of warbling!

Onnights with a full moon, male Sage Thrashers have been known to proclaim theirlong-winded songs all night. But the North American record-holder may well bethe Red-eyed Vireo. One such vireo delivered its short song over 22,000 timesin ten hours!

We’veall heard about the “early bird” getting the “worm.” We know it as sound adviceabout initiative and timely action. And we can almost see that robin leaningback and tugging that recalcitrant worm out of the ground. Research shows,however, that birds dining early and heavily may lower their life expectancy. Astudy of three North American woodland bird species found that sociallydominant birds stay lean during the day and then stoke up when it’s mostimportant- later in the day, before a cold night. At night, birds avoidhypothermia by metabolizing fat. And by staying lean through most of the day,dominant birds are more agile in avoiding predators.

Subordinatebirds have to look for food whenever and wherever they can find it, and carryfat on their bodies to hedge against unpredictable rations. Dominant birds,which can push subordinates off food, can choose when they eat and so lessentheir odds of being eaten themselves.

Therefore,at least in the woodland bird’s world, the revised moral might read: “Get the wormlate in the day- you’ll sleep better and live longer.”

Somebirds are very well known. A few are even legendary.

Theancient Greeks and Egyptians described a mythical bird called the Phoenix, amagnificent creature that was a symbol of renewal and rebirth.

Accordingto legend, each Phoenix lived for 500 years, and only one Phoenix lived at atime. Just before its time was up, the Phoenix built a nest and set itself onfire. Then, a new Phoenix would rise from the ashes.

Boththe Greeks and Egyptians associated the phoenix with the sun. One myth says thedawn song of the Phoenix was so beautiful, the sun god Apollo would stop hischariot- and the sun- to listen.

Ancientsources differ on the bird’s size and color. Some say it was the size of aneagle; others, bigger than an ostrich- with bright red and gold or maybe evenpurple feathers. All agree it- definitely had a golden aura. And in everyversion, it was exotic, literally one of a kind.

PoetWallace Stevens imagined the mythical “gold-feathered bird” perched in a palmtree. He wrote:

“Thebird sings. Its feathers shine.

Thepalm stands on the edge of space.

Thewind moves slowly in the branches.

Thebird’s fire-fangled feathers dangle down.”

Hello, this isWild Suzhou.

Today, we will betalking about ambergris, an interesting product that comes from the intestinesof a sperm whale and has some unexpected uses.

First, let’s talkmore about what ambergris actually is. It is also called grey amber, which isjust a translation of the originally French word. This waxy, usually greysubstance is formed in the bile ducts of a sperm whale’s intestine, and similarto poop, it exits the body the same way. Scientists believe that the reasonambergris exists is that it acts as a waxy coating over sharp objects, such assquid beaks, that sperm whales will eat. By doing this, these sharp and usuallyhard-to-digest objects will not scratch and hurt the inside of the whale’sintestine.

But, what isambergris used for? In some places, especially in East Asia, ambergris has beenused as traditional medicine. But more common and more surprising is thatambergris used to be a common ingredient in perfume. First, it is used as afixative, meaning that the smell would last longer on the wearer once they hadput the perfume on. It is also described to have a pleasant and earthy smell,making it desirable for luxury perfume makers, especially since ambergris is sorare. Ancient Egyptians would burn ambergris as incense, whereas modernEgyptians use it in cigarettes.

However, ambergrisis also incredibly rare. It’s estimated that only around 1 percent of spermwhales will ever make ambergris. Also, it will usually float around in theocean for several years before it reaches the shore for someone to harvest it.Because of its rarity and also because of legal questions surrounding howethical it is to harvest ambergris, most perfume makers have stopped usingambergris and instead turned to synthetic alternatives that work just as well.

For Wild Suzhou,I’m Ciana, thanks for listening and see you next time.

Youmight think the first bird species that humans raised in captivity would be arelatively small one, like a chicken.

Butevidence suggests that people in New Guinea reared the cassowary, often calledthe world’s deadliest bird, as much as 18,000 years ago, long before thedomestication of chickens.

Theremains of cassowary eggs and bones at archaeological sites in New Guineaindicate that people gathered the eggs, possibly allowing the more mature eggsto hatch into chicks.

Allcassowaries possess fearsome sharp toes that have been known to kill orseriously injure humans. While Northern and Southern Cassowaries can reachheights of five feet or more, the Dwarf Cassowary stands just three and a halffeet tall.

Researcherssuspect that by collecting nearly-hatched cassowary eggs, probably from theDwarf Cassowary, people could have easily reared their chicks. Today in NewGuinea, captive cassowary chicks become imprinted on their human carers,allowing people to raise them to adulthood.

Cassowariesmay not be the cuddliest of birds. But people found a clever way to live besidethem long ago.

It’sspring, and the Ruby-crowned Kinglet’s loud, rollicking song echoes from theforest edge in northern and western lowlands. Listen carefully, and you canhear three distinct parts of its song.

Thistiny powerhouse of a singer is one of the smallest songbirds on the continents,weighing in at just a little more than half a chickadee. Mostly green and hardto spot, flitting from twig to twig, it hovers in mid-air as it catches tinyinsects. The green crown-feathers on the male kinglet conceal a swatch of redones. When in the mood to sing, he raises this narrow, crimson crest. Thekinglet’s Latin name suits it well: Regulus calendula- the “glowing littleking,” a regal luster that points to his ruby crown, but could also describehis song.

TheRuby-crowned Kinglet turns up his spring song only in the lowlands. Later thismonth, he’ll depart to sing- and nest- at mile-high altitudes in our mountainforests.

Arobin tugging an earthworm from the ground is a symbol of spring. But that wormit’s eating hasn’t always been here.

Whenglaciers pushed south into what is now the U.S. around 20,000 years ago, theyscraped off the soil layer and spelled the end of native earthworms except inthe southern states. So that earthworm plucked by the robin is probably arelatively new arrival, most likely a species Europeans conveyed to theAmericas in plant soil or in the ballast of ships.

Soif not earthworms, what were robins feeding their chicks before Europeansarrived? Well. Probably some of the more than a hundred kinds of insects andother invertebrates, as well as berries, that robins are known to eat.

Robinsprefer to forage in short grass to avoid potential predators. But after thelast ice sheets melted back, where was the short grass they liked? Onespeculation is that prehistoric bison, horses and mammoths grazed heavily inplaces, creating robin-friendly landscapes.

Justas robins now share pastures with cows, perhaps 15,000 years ago they hoppedamong giant bison or woolly mammoths.