Do shrimp have a heart? Ginger, Kerrville, Texas,
they do. It's a longitudinal blood vessel lying along the middle of the
shrimp's back. Shrimps have a blood system (like insects) that opens into the
body cavity so that all the organs are bathed in blood.
Do giraffes see in colour ?
Jackson, Arusha, Tanzania
Yes, they distinguish between red, orange, yellow-green, green, blue
Do ants blink? Asks Will aged 4, UK
Ants (like all insects) don't have eyelids so they can't blink.
here for more about
insect eyes. They're amazing.
Can giraffes swim? The established wisdom seems to be that
they can't. However, someone (who left an online comment) saw giraffes swimming
on a TV program. I would love to know for sure. Zen, London, England
Probably they can, but rarely do. In fact, nobody has ever seen
giraffes swim, says NatureWildlife.com, but we have found wild giraffes on an
island surrounded by water at least 14 feet (4 m) deep.
Do parrots mate
for life? Joe, Lakeworth, Florida, USA
Most of them do, Joe. Here's a
parrot info link.
Do wild Florida rabbits mate for life?
Luke, North Port, Florida, USA
I'm surprised to find out both wild rabbits and rabbits in captivity
mate for life.
What are baby foxes
called? What is a group of foxes called? Cheryl,
Colorado Springs, Colorado, USA A Baby fox is called a kit, cub or
pup. A group of foxes is called a skulk or leash. Click here
for more about
baby animal names.
Which aquatic animal changes its colour faster than chameleon?
Deepak, Bangalore, Karnataka, India The
cuttlefish (squid-like marine mollusks) changes color as he swims over
different surfaces --- that's fast --- much faster than a chameleon. And
he can assume even more intricate patterns than the chameleon.
Do cows get
hit by lightning? Jane Miami, Florida,
USA Yes. Here's a site telling about many
dieing along an electric fence hit by lightning.
What does a octopus do when it is threatened by a predator?
Brittany, Orange, New South Wales, Australia It depends on
the octopus. The extremely toxic blue-ringed octopus displays his
brilliant blue rings to warn a predator off.
octopus have a pair of 'eye spots' that they can flash", says biologist
Roy Caldwell. This may startle predators just as the
eyespots on a moth do.
Most octopuses release a reservoir of dark
inky dye, which might serve as a smoke screen and/or be noxious
disabling the predators chemosensory organs. Other species can release ink
mixed with mucus. This forms a brown or black glob that hangs in the water
and looks somewhat like the octopus. Often, as the octopus releases the
deceptive glob, it changes color (usually to white) and gets away. The
predator attacks the glob and gets nothing more than a mouth full of bad
Octopuses also can change their skin coloration to
Several octopus species drop their arms off their body
when attacked. "The wiggling autotomized arms will even lock onto the
predator with its suckers," says Caldwell. "This is usually
sufficiently distracting to allow the octopus to escape." Re-growing lost
arms is a snap for an octopus.
I have a female cockatiel, 3 years
old. How come she lays eggs? Since there is no male, at all and never has been,
this is very strange! Rachael, Shoalhaven, NSW, Australia All
female birds lay eggs, whether or not there's a male present. The eggs are
unfertilized in your case, and won't hatch. It's important to let your bird sit
on her eggs and not to throw the eggs away because otherwise she might keep
laying eggs to replace the ones thrown out, and get exhausted.
If you let her sit on the eggs undisturbed, she'll probably reach a total of
between 6 and 10 eggs, which she will sit on for several weeks until she loses
interest. When she neglects sitting on the eggs for several consecutive days,
then you know it's safe to toss the eggs out. Female cockatiels will go through
this egg-laying process once or twice a year.
Where do birds sleep in the
winter in the Northeast? Why don't we see birds' nests?
Ruth, Wilmington, Delaware, USA
Birds sleep where they safely can stay warm. Their feathers are their primary
defense against cold. Some ducks sleep in icy water. Bobwhite sleep on the
ground. Crows and turkeys roost in trees. Screech-owls and many other
cavity-nesters sleep in their favorite cavities and nestboxes.
We don't see nests so often in the winter because nests are used primarily
for laying eggs and hatching and raising chicks. Birds breed (and build nests)
during seasons timed so their young grow up when food is most plentiful.
For most songbirds, this is in the spring.
How do scientists know what sounds dinosaurs actually made? My 5 month old
makes "dinosaur noises" all the time which lead me to ask my husband this
question. He didn't know either. Annie, Fort Wayne,
dino noises are just guess work to, for example, make a movie. But some
simulations may come close to the real thing. One such is based on an
almost complete fossil crest of Parasaurolophus dinosaur, unearthed near
Farmington in northwest New Mexico.
Scientists at Sandia Lab in Albuquerque analyzed the crest using a CT scan,
and found trombone-like loops and other air chambers. They made a computer
model of the crest, based on the CT scan information. Then, knowing the
size and shape of the air passages, they were able to guess what sounds the
passages could produce --- the tones and pitches. From there they
generated tones and pitches to actually sound like a dino --- a resonating
low-frequency rumbling sound that can change in pitch like a bird, perhaps
calling to a mate or declaring territory. Click for the
sound of a
Use Digital Paleontology to Produce Voice of Parasaurolophus Dinosaur
Why do aircraft use electrical components that run at 400 Hz frequency?
The higher 400 Hz frequency cause [up to seven times] more reactive
losses compared to 60Hz frequency. So why do aircraft use it?
Bharti, Faridabad, India The reason aircraft use 400 Hz
frequency instead of 60 Hz is to save weight and volume. 400-Hz devices are
usually smaller and lighter. The lighter the aircraft, for a given power
system, the higher it's performance. That's why Charles Lindbergh didn’t
take a radio when he flew across the Atlantic.
Are the photons or electrons (not sure which) that we see in TV
snow/static left over from the big bang? Maria, New York State,
Yes (the radiation is microwaves now). "Turn your television to an 'in
between' channel, and part of the static you'll see is the afterglow of the
big bang," says NASA.
My comment has to do with seeing the residue of the Big Bang in snow on the TV
screen. A good answer, but becoming vanishingly small in applicability. I think
it applies only to *analog* TVs.
There are three things that keep it from being approximately correct for digital
TVs -- the nonrandomness that comes from the screen's inherent quantization,
effects of noise rejecting RF digital filters in the receiver, and the way that
PLL digitally synthesized signals work in the presence of little or no input
from the RF and IF stages of the receiver. In digital TVs, what the snow
represents is a bad digital approximation to wandering around in the quantum
noise weeds of the transistors in the PLL synthesis circuitry.
BTW, I have an experimental validation of the nonrandomness of snow on digital
TV screens. Get an old analog TV and tune it to no channel and get a nice
uniform field of snow. Lean close to the screen so the screen image fills your
visual field and stare at it without blinking for as long as you can. Soon you
will start seeing circular patterns in the snow. These are not actually there;
they are being created by your optic nerves and brain in an attempt to deal with
pure randomness of input. (This has a sensory analogy in Delirium Tremens...) If
you try the same experiment with a digital TV you will find it is much harder,
if not impossible, to get the circular patterns to begin forming. This is
because the human nervous system is happy with nonsensical input as long as it
is not truly random. Bob, Marietta, Georgia
What is the time frame for a black hole? If a black hole is infinite or
near infinite in density does that mean that it's time frame relative to us is
stopped or very slow? Tom, Jersey City, New Jersey,
gravity of a black hole is, indeed, enormous — so great it bends light back
down into the black hole, says physicist
Rod Nave. Light cannot escape the event horizon. Suppose
daredevil you are in a spacecraft, and decide to dive into the black hole.
How does time pass for you and me, far away watching? You perceive no
difference in how time passes. In you go, time passes normally.
But I see a big difference. The closer your spacecraft gets to the event
horizon, the more the hole's gravity bends the light reflected from your
spacecraft, and the longer that reflected light takes to reach me. It
seems to me that time has slowed, and slows more until it stops as you reach
the event horizon. There, at the horizon, the light from your craft
bends back down into the black hole, and I never see you enter the hole.
What is the the name of the new planet which is found in space? Priya,
Dubai, United Arab Emirates (U.A.E.) The planet's name is Gliese
581 C — a name derived from its sun, the dim and distant red-dwarf star
(Gliese 581), about 20.5 light-years away. The planet is about 50
percent bigger than Earth and five times more massive. It is the first
extra-solar planet found that could support life. Gliese 581 C may have
liquid water, announced astronomer Stephane Udry of the Geneva Observatory in
Switzerland on April 24, 2007.
A Planck length to a meter is smaller or
bigger than a millimeter is to the size of the universe?
RV Ramani, Bangalore, India
The ratio (1.6x10^-35) of a Planck length (to a meter is smaller than the
ratio (6.7x10^-34) of a millimeter is to the size (width) of the universe, but
it's surprisingly close (0.02).
We are comparing a very small number — the smallest length with physical
meaning — to an extremely big number (the width of the Universe). That is
interesting, though fraught with peril. What, exactly is the size
of the Universe? The mathematics program,
Wolfgram, uses a different number and finds a different answer:
(1meter/(planck's length)) / ((1000/1meter) (size of the universe in meters))
= 70,000 instead of 0.02. Take your pick.
The Planck length is the scale at which classical ideas about gravity and
space-time cease to be valid, and quantum effects dominate. This is the ‘quantum
of length’, the smallest measurement of length with any meaning.
What would be the best way to sanitize toothbrushes? Leigh,
Closter, New Jersey According to the
American Dental Association, sanitizing toothbrushes is a waste of time.
At least, it does nothing to improve health. They recommend replacing a
toothbrush in three to four months.
Reader's comments: Actually a
co worker that is a microbiologist did a test to help her
daughter in a high school science project and found that you should actually
replace your tooth brush 1 time per week (she said just go to the dollar store
and get cheap tooth brushes) because when she ran micro tests on the brushes it
was amazing that there was coliform on the brushes very quickly just from being
in the same room as the toilet and the aresol created from flushing the toilet
spread the bacteria everywhere and toothbrushes were an excellent haven for
these germs to grow. Joe, Rochester, New York.
Under "Humans" - What's the best way to sanitize a toothbrush, try OraQuel,
American Dental Association has in fact published several reports stating links
exist between improper oral care, cardiovascular and other serious illness.
Links are posted on the site to many reports in respected journals.
What is the national language in England? Kikki, Plantation,
Flordia England, like the USA, has no official national
language (designated by legislation)
My mother has dark brown eyes. My father
has blue-green eyes that change. When I was born my eyes appeared black. For
most of my childhood, they appeared dark like my mother. But when I became a
pre-teen, they turned hazel (brown and green). Is that normal?
Tori, Graniteville, USA
It is normal for eyes to change as yours has, Tori, but such color loss can
also be the result of an eye disease. So you might have a doctor check your
eyes. Please click here to read more about changing eye color and hazel
What exactly are hazel eyes,
and what color are they? WonderQuest
I have two girl babies. But I wish a boy. Can medical science help me
to born a boy baby? Saima, Lahore, Pakistan None of the
easy procedures that we have developed to influence the sex of the new born
has been proved to work, according to the rigorous standards of medical
journals. But because they haven't been proved effective, doesn't mean
they don't actually help.
If you want to try, click
for some tips on how and when to have sex so it favors a boy-child. They
might work (or might not).
Why do humans turn red when they are embarrassed? Is there an evolutionary
reason? 'Wattsya', World
There is an evolutionary reason. When a person is embarrassed, a
primitive part of his mind kicks in, thinking the body's in danger. It's
a subtle reaction --- one we don't understand well. But, thinking
'moderate danger', the brain tells the body to release adrenalin (also: widen
pupils, beat the heart faster, breath more rapidly, sweat and cause the hair
to stand-up), in preparation for flight. A side effect to the adrenalin
release causes blood vessels in the face swell, which causes our face to turn
Using a telescope, if I could look into a mirror located far away from the
earth, would the reflection I see be in the past?
James, St. Louis, Missouri, USA
Yes, it would, James, because light travels at a finite speed; it takes
time to travel to the far away spot and back again. You would see your
reflected self from the past.
I have been arguing with my uncle and others
for years that the speed of sight is much much faster than the speed of light.
If I was looking at a star, say 100 light years away, and it exploded, I would
see it instantly as it happened ??? For instance, if I threw a rock into a lake,
I would see the splash (or explosion) as it happened, but it would take the
ripples quite awhile to reach the shore. Similarly, I understand that it would
take 100 years before the light waves would reach Earth. What do you
think? Bill, Huber Heights, Ohio, USA
I see the analogy you're making but it doesn't quite work because
light waves are
fundamentally different than water waves. Also, you see the splash
because light hits the splashed water, reflects from it and travels to your
eyes. So, you don't see the splash instantaneously. If you throw the
rock 20 feet (3 m), it takes light about 10 billionths of a second to travel the
20 feet to your eyes. That's fast but not instantaneously.
Similarly, you don't see the star's explosion instantaneously. It's the
same calculation (distance / speed = travel time). The vastly greater
distance takes greater time, in fact, 100 years. No information or object
can travel faster than light speed. Actually the
speed of sight is even slower than the speed of light. You need to
tack on another 50 milliseconds from the time light reaches your eye for the
brain to sense it and see the object.
Does a person get more wet running through
the rain or walking through the rain (given the same distance walking or running
from point A to point B, number of raindrops, steadiness of rain, and other
variables all constant.) Mark, Phoenix, Arizona,
don't walk to stay about 40% drier.
How are mass and weight related? April, Whitesville,
An object's mass tells how much there is of an object, and its weight
tells how much attraction due to gravity there is between the Earth and the
object. Weight is related to both mass and gravity.
But how are mass and weight related? The greater the mass, the greater
is its weight, but the opposite is not necessarily true. An object with a
greater weight may not have a greater mass. For example, you have the same mass
on Earth as you do on the Moon, but you weigh much less on the Moon.
How does exposure to sunlight cause colors to fade in things like clothing
and paintings? Emily, Albuquerque, New Mexico
Dye molecules can change when they absorb light energy. If the molecule
changes into a different molecule (via a physical or chemical reaction), it
won't reflect light as it did before. It will be a different color.
Dye molecules that produce bright colors are more prone to change because
sometimes we must use dyes that are unstable to get the color intensity we want.
For example, to get a bright blue we want a dye that absorbs all of the red
light and none of the blue. Copper sulfate does the job but is too toxic
for clothes (it's used to kill plants and bacteria). So we must use a less
stable chemical, which, unfortunately, changes as it absorbs the red light.
Its color, therefore, lessens and fades.
Is a peanut a fruit? Mikayla, Smithfield, North Carolina,
Yes. A peanut is the fruit of the peanut plant. After the
plant sprouts from a planted seed, and grows about 18 inches, yellow flowers
appear and bloom for about a month. After fertilization and the flowers
fade, the young fruit forms a pointed stalk called a peg. The 'digging stick'
peg points and grows downward. The fruit (i.e., peanuts) develop a woody outer
shell (the peanut shell), and the pointed fruits bury themselves — in the
I was surprised when I took first flight in my life and, when the plane
reached above clouds, saw the temperature
display read -23C degrees. Could you
please explain the reason? Siba, Abu Dhabi,
United Arab Emirates (UAE)
The Sun’s rays pass right through the atmosphere. Earth’s surface absorbs
them and re-radiates the energy in the form of heat that air can absorb. Thus,
the Sun warms the air by warming the ground. Air closest to the Earth’s surface
is, in general, warmest. Air above low clouds (plane cruising altitude) is
poorly warmed and, therefore, cold. Related question:
is it colder in the mountains?
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