living organism that feeds on organic matter, typically having
specialized sense organs and nervous system and able to respond rapidly
Adjective: Of, relating to, or characteristic of animals: "animal life".
The word "animal" comes from the Latin word animal (meaning with soul, from anima, soul).
In everyday colloquial usage, the word usually refers to non-human animals.
Frequently only closer relatives of humans such as mammals and other vertebrates are meant in colloquial use. The
biological definition of the word refers to all members of the Kingdom
Animalia, encompassing creatures ranging from insects to humans.
The Mystery of the Deep
Life on Earth does not just consist of what we see on land. There is also a rich undersea life
far from our sight.
Each with its own unique design, the oceans are home
to very different kinds of sea creatures.
To such an extent, in fact,
that the millions of species in the seas are little by little increasing
with every new dive.
term 'Deep Sea refers to organisms that live below the photic zone of
These creatures must survive in extremely harsh conditions;
such as hundreds of atmospheres of pressure, small amounts of oxygen,
very little food, no sunlight, and constant, extreme cold.
creatures have to depend on food floating down from above. These
creatures live in very harsh environments such as the abyssal or hadal
zones, which, being thousands of meters below the surface, are almost
completely devoid of light. The water is very cold (between 3 and 10
degrees Celsius, or 37 and 50 degrees Fahrenheit), and has low oxygen
to the depth, the pressure is between 20 and 1,000 atmospheres.
Creatures that live thousands of feet deep in the ocean have adapted to
the high pressure, lack of light, and other factors.
have explored less than 2% of the ocean floor, and dozens of new
species of deep sea creatures are discovered with every dive.
submarine DSV Alvin—owned by the US Navy and operated by the Woods Hole
Oceanographic Institution (WHOI) in Woods Hole,
Massachusetts—exemplifies the type of craft used to explore deep water.
16 ton submarine can withstand extreme pressure and is easily
maneuverable despite its weight and size.
However, studying deep sea
creatures is problematic, since with the extreme change in pressure, and
environment in general, these creatures can't survive for very long, if
at all, on the surface. This makes in depth research difficult
because so much of what we want to know about only occurs while the
creature is alive.
Recent developments have allowed scientists to look
at these creatures more closely, and for a longer time.
biologist, Jeffery Drazen, has explored a solution, a pressurized fish
trap. This captures a deep-water creature, and adjusts its internal
pressure slowly to surface level as the creature is brought to the
surface, in hopes that the creature can adjust.
Fish With Transparent Head
For the first time, a large Pacific barreleye fish - complete with
transparent head - has been caught on film by scientists using remotely
operated vehicles at the Monterey Bay Aquarium Research Institute. The
deep-sea fish's tubular eyes pivot under a clear dome.
Barreleyes, also known as spook fish (a name also applied to several species of chimaera), are small, unusual-looking deep-sea osmeriform fish comprising the family Opisthoproctidae.
Found in tropical-to-temperate waters of the Atlantic, Pacific, and Indian Oceans, the family contains thirteen species in six genera (four of which are monotypic).
These fish are named for their barrel-shaped, tubular eyes which are generally directed upwards to detect the silhouettes of available prey; however, according to Robison and Reisenbichler these fish are capable of directing their eyes forward as well. The family name Opisthoproctidae is derived from the Greek words opisthe ("behind") and proktos ("anus").
All species have large, telescoping eyes which dominate and protrude from the skull, but are enclosed within a large transparent dome of soft tissue. These eyes generally gaze upwards, but can also be directed forwards.
The opisthoproctid eye has a large lens and a retina with an exceptionally high complement of rod cells and a high density of rhodopsin (the "visual purple" pigment); there are no cone cells.
To better serve their vision, barreleyes have large, dome-shaped transparent heads; this presumably allows the eyes to collect even more incident light and likely protects the sensitive eyes from the nematocysts (stinging cells) of the siphonophores from which it is believed the Barreleye steals food.
It may also serve as an accessory lens (modulated by intrinsic or peripheral muscles), or refracts light with an index very close to seawater. A recent study disclosed that Dolichopteryx longipes is the only vertebrate known to use a mirror (as well as a lens) in its eyes.
The Proboscis Monkey of Borneo
The Proboscis monkey's search for tender new leaves must take it across
the rivers of Borneo. But beneath the murky waters lie one of earth's
most fearsome predators, the crocodile.
Proboscis Monkey (Nasalis larvatus) is also known as the Monyet Belanda
in Malay, the Bekantan in Indonesian or simply the Long-nosed Monkey.
It is a reddish-brown arboreal Old World monkey that is endemic to the south-east Asian island of Borneo.
belongs in the monotypic genus Nasalis, although the Pig-tailed Langur
has traditionally also been included in this genus - a treatment still
preferred by some.
While the official Indonesian name for this
monkey is Bekantan, an Indonesian nickname is 'monyet belanda', meaning
'Dutch monkey' or 'Orang Belanda', the Indonesian word for 'Dutchman',
as Indonesians noticed the Dutch colonisers often also had a large belly
A distinctive trait of this
monkey is the male's large protruding nose, from which it takes its
name. The big nose is thought to be used to attract females and is a
characteristic of the males, reaching up to 7 inches in length. The
females also have big noses compared to other monkey species, but not as
big as the males.
attracting mates, the nose serves as a resonating chamber, amplifying
their warning calls. When the animal becomes agitated its nose swells
with blood, making warning calls louder and more intense.
Monkey belong to the order of Primates, from the family Cercopithecidae
and subfamily Colobinae.
According to Bennett & Gomber
(1993), in the Old World, these monkeys are divided into two groups
known as cercopithecines and colobines.
Proboscis Monkey are colobines.
Males are much larger than females, weighing up to 24 kg (53 pounds) and
reaching 72 cm (28 inches) in length, with a tail of up to 75 cm in
Females are up to 60 cm long, weighing up to 12 kg (26
lb). This large sexual dimorphic difference is greater than in any other
primate. The nose is a noticeable feature even on infants.
adult Proboscis Monkey is mainly reddish-brown, with grayish limbs.
According to Burnie (2001), young Proboscis Monkeys have a blue face,
blackish fur and a relatively normal sized nose at birth.
they grow older, fur coloration changes and the nose grows. Adult males
have a large and fleshy nose which overhangs its mouth, but the female
Proboscis Monkey does not have a large nose in comparison to the male.
Tarsiers are the only extant entirely carnivorous primate on Earth: they are primarily insectivorous, and catch insects by jumping at them.
They are also known to prey on small vertebrates, such as birds, snakes, lizards, and bats.
they jump from tree to tree, tarsiers can catch even birds in motion.
Although the group was once more widespread, all the species living
today are found in the islands of Southeast Asia.
are small animals with enormous eyes; each eyeball is approximately 16
mm in diameter and is as large as their entire brain. Tarsiers also have
very long hind limbs.
In fact, their feet have extremely
elongated tarsus bones, from which the animals get their name. The head
and body range from 10 to 15 cm in length, but the hind limbs are about
twice this long (including the feet), and they also have a slender tail
from 20 to 25 cm long.
Their fingers are also elongated, with
the third finger being about the same length as the upper arm. Most of
the digits have nails, but the second and third toes of the hind feet
bear claws instead, which are used for grooming. Tarsiers have very
soft, velvety fur, which is generally buff, beige, or ochre in color.
have never formed successful breeding colonies in captivity, and when
caged, tarsiers have been known to injure and even kill themselves
because of the stress. One site in the Philipine Island of Bohol is
having some success restoring tarsier populations. The Philippine
Tarsier Foundation has developed a large semi-wild enclosure that uses
lights to attract the nocturnal insects that make up the tarsier's diet.
2008 described Siau Island Tarsier is regarded as critically endangered
and was listed among the 25 most threatened primates by Conservation
International and the IUCN/SCC Primate Specialist Group in 2008.
Malaysian government protects tarsiers by listing them in the Totally
Protected Animals of Sarawak, the Malaysian state in Borneo where they
are commonly found.
The Pygmy Marmoset or Dwarf Monkey (Cebuella
pygmaea) is a New World monkey native to the rainforest canopies of
western Brazil, southeastern Colombia, eastern Ecuador, eastern Peru,
and northern Bolivia.
is one of the smallest primates, and the smallest true monkey, with its
body length ranging from 14 to 16 centimetres (5.5 to 6.3 in)
(excluding the 15-to-20-centimetre (5.9 to 7.9 in) tail).
Males weigh around 140 grams (4.9 oz), and females only 120 grams (4.2 oz).
Pygmy Marmoset uses special types of communication to give alerts and
warning to its family members. These include chemical, vocal, and
physical types of communication.
A trill is used to
communicate over long distance. A sharp warning whistle and a clicking
sound signal danger to their family members. A J-call is a series of
fast notes repeated by the caller and is used at medium distances.
marmosets live 11-12 years in the wild, but in zoos, they live into
their early twenties. Marmosets often live in groups made up of an adult
pair and its offspring; ranging from 2-6 members. Young marmosets
typically remain in the group until after 2 consecutive birth cycles.
Weedy Sea Dragons
These two could teach Strictly Come Dancing a thing or two. Named for
their uncanny resemblance to the plant life around them, a male weedy
seadragon seduces a female with some very fancy fin work.
Phyllopteryx taeniolatus, the Weedy
Seadragon or Common Seadragon, is a marine fish related to the
seahorse. It is the only member of the genus Phyllopteryx.
later, however, its the male who's left carrying the eggs.
off the coast of south Australia, weedy seadragons (Phyllopteryx
taeniolatus) are the only known species along with sea horses and
pipefish - where the male carries the eggs.
Although the eggs start out
in the female, she lays about 120 of them onto the tail of the male
where they are then fertilized and develop until they hatch.
It is found
in water 3 to 50 m deep around the southern coastline of Australia,
approximately between Port Stephens, New South Wales and Geraldton,
Western Australia, as well as around Tasmania.
are named for the weed-like projections on their bodies that camouflage
them as they move among the seaweed beds where they are usually found.
Seadragons can reach 45 cm in length. They feed on tiny crustaceans and
other zooplankton, from places such as crevices in reef, which are
sucked into the end of their long tube-like snout.
lack a prehensile tail that enables similar species to clasp and anchor
themselves. Phyllopteryx taeniolatus swim in shallow reefs and weed
beds, and resemble drifting weed when moving over bare sand.
seahorses and pipefish are the only known species where the male
carries the eggs.
The male of the species carries the fertilized
eggs, attached under his tail, where they are incubated for about eight
weeks. The young are independent at birth, beginning to eat shortly
Mating in captivity is rare since researchers have yet to
understand what biological or environmental factors trigger them to
In captivity the survival rate for Weedy Seadragons
is about 60%. A more cryptic relative of the Weedy Seadragon is the
Leafy Seadragon, Phycodurus eques. In the November 2006 issue of
National Geographic magazine, marine biologist Greg Rouse is reported as
investigating the DNA variation of the two seadragon species across
The Aquarium of the Pacific in Long Beach,
California, in the USA; the Melbourne Aquarium in Melbourne, Victoria,
in Australia; and the Tennessee Aquarium in Chattanooga, Tennessee, in
the USA, are the only facilities in the world to have successfully bred
Weedy Seadragons in captivity, though others occasionally report egg
As of June 2008, the Georgia Aquarium in Atlanta, USA
had a pregnant seadragon, which was expected to give birth in early-mid
July. The Weedy Seadragon is the marine emblem of the Australian State
These vampire bats have heat sensors in their noses-all the better for
finding the sweet spot on a sleeping victim - and sipping half their
weight in blood.
bats are bats whose food source is blood, a dietary trait called
hematophagy. There are three bat species that feed solely on blood: the
Common Vampire Bat (Desmodus rotundus), the Hairy-legged Vampire Bat
(Diphylla ecaudata), and the White-winged Vampire Bat (Diaemus youngi).
All three species are native to the Americas, ranging from Mexico to
Brazil, Chile, and Argentina.
Because of differences
between the three species, they have each been placed within a different
genus, each consisting of one species.
In the older literature, these
three genera were placed within a family of their own, Desmodontidae,
but taxonomists have now grouped them as a subfamily, the Desmodontinae,
in the American leaf-nosed bat family, Phyllostomidae.
that the three known species of vampire bat all seem more similar to one
another than to any other species suggests that sanguivorous habits
(feeding on blood) evolved only once, and that the three species may
share a common ancestor.
Unlike fruit-eating bats, the vampire
bat has a short, conical muzzle. It also lacks a nose leaf, instead
having naked pads with U-shaped grooves at the tip. The common vampire
bat also has specialized thermoreceptors on its nose, which aids the
animal in locating areas where the blood flows close to the skin of its
A nucleus has been found in the brain of vampire bats that
has a similar position and similar histology to the infrared receptor
of infrared-sensing snakes. Vampire bats generally have small ears and a
short tail membrane. Their front teeth are specialized for cutting and
their back teeth are much smaller than in other bats.
digestive system is adapted to their liquid diet, and their saliva
contains a substance, draculin, which prevents the prey's blood from
clotting. The vampire bats do not suck blood, but rather lap the blood
at the site of the haemorrhage (where the prey is bleeding).
inferior colliculus, part of the bat's brain that processes sound, is
well adapted to detecting the regular breathing sounds of sleeping
animals that serve as their main food source.
Vampire bats are
believed to be the only species of bats in the world to "adopt" another
young bat if something happens to the bat's mother. Vampire bats also
share a strong family bond with members of the colony, which is believed
to be why they are the only bats to take up this adoption
Another unique adaptation of vampire bats is the
sharing of food. A vampire bat can only survive about two days without a
meal of blood, yet they cannot be guaranteed of finding food every
night. This poses a problem, so when a bat fails to find food it will
often "beg" to another bat for food.
The "host" bat may regurgitate a
small amount of blood to sustain the other member of the colony. This
has been noted by many naturalists as an example of reciprocal altruism
bats hunt only when it is fully dark. Like fruit-eating bats, and
unlike insectivorous and fish-eating bats, they emit only low-energy
The common vampire bat feeds mostly on the blood
of mammals (including humans), whereas both the hairy-legged vampire bat
and white-winged vampire bat feed on the blood of birds.
Once the common vampire bat locates a host, such as a sleeping mammal, it lands and approaches it on the ground.
bats are very agile and a recent study found that common vampire bats
can, in addition to walk, run at speeds of up to 7.9 km per hour (4.9
miles per hour). They locate a suitable place to bite using their
infrared sensors. They then create a small incision with their teeth and
lap up blood from the wound.
"The most common species, the South
American vampire (Desmodus) is not fastidious and will attack any
warm-blooded animal. The white-winged vampire (Diaemus) appears to have a
special preference for birds and goats. In the laboratory it has been
impossible to feed Diaemus on cattle blood."
If there is fur on
the skin of the host, the common vampire bat uses its canine and cheek
teeth like a barber's blades to shave away the hairs. The bat's
razor-sharp upper incisor teeth then make a 7mm long and 8mm deep cut.
upper incisors lack enamel, which keeps them permanently razor
sharp.The bat’s saliva, which is injected into the victim, has a key
function in feeding from the wound. The saliva contains several
compounds that prolong bleeding, such as anticoagulants that inhibit
blood clotting, and compounds that prevent the constriction of blood
vessels near the wound.
typical female vampire bat weighs 40 grams and can consume over 20
grams (1 fluid ounce) of blood in a 20-minute feed. This feeding
behaviour is facilitated by its anatomy and physiology for rapid
processing and digestion of the blood to enable the animal to take
flight soon after the feeding.
The stomach lining rapidly absorbs
the blood plasma, which is quickly transported to the kidneys from
where it passes to the bladder for excretion. A common vampire bat
begins to expel urine within two minutes of feeding.
shedding much of the blood's liquid makes taking off from the ground
easier, the bat still has added almost 20-30% of its body weight in
To take off from the ground, the bat generates extra lift
by crouching and flinging itself into the air. Typically within two
hours of setting out, the common vampire bat returns to its roost and
settles down to spend the rest of the night digesting its meal.
urea from protein is thereby excreted via the urinary system of the
vampire bat aided by hormones to make concentrated urine that consists
of concentrated urea in small amounts of water.
Vampire bats tend
to live in colonies in almost completely dark places, such as caves,
old wells, hollow trees, and buildings. They range in Central to South
America and live in arid to humid, tropical and sub tropical areas.
Colonies can range from a single individual to thousands, often roosting
with other species of bat. They will almost always have only one
offspring per breeding season.
Each colony will typically have
only one reproducing male, with around twenty females and their
offspring. Each individual needs a blood meal at least once every few
days. If a bat fails to get adequate food during its foraging, it may
contact another vampire bat in its colony to induce a food donation. The
food exchange occurs mouth-to-mouth in an activity similar to kissing.
Vampire bats can live up to nine years in the wild and up to 19 in