1 Coelacanth
The Coelacanth is the most famous of all “living fossils” and deserves
to be #1 in this list, because it is the best example of a “Lazarus
taxon”, this is, animals that were supposed to be long extinct and are
unexpectedly found to be alive. Coelacanths were supposed to have become
extinct in the Cretaceous period, along with the dinosaurs, but in
1938, a live specimen was caught in South Africa. Since then, more
specimens have been seen and photographed, and a second coelacanth
species was even found in Indonesia in 1999. Coelacanths are large
predators, up to 2 meters (6' 6?) long; they feed on smaller fish,
including small sharks, and are usually found in deep, dark waters.
Although rarely captured and consumed due to their horrible taste,
coelacanths are critically endangered nowadays.
2 Polypterus Senegalus
These african fish are often called “dinosaur eels”, due to their
reptilian appearance and serrated dorsal fin, reminiscent of some
dinosaurs’ spiked backs. They are not really eels, but members of the
bichir family. Bichirs were already around in the Cretaceous, so the
“dinosaur” part of their name is actually fitting in a way. Although
often sold as exotic pets, dinosaur eels are prone to escaping their
fish tanks. They can survive out of the water for long periods of time
as long as their skin remains wet, which enables them to wander far away
from their tank.
3 Alligator Gar
This formidable, thick scaled predator is found in the southern US and
northern and eastern Mexico, being the largest freshwater fish in North
America (although it sometimes wanders into the sea). It can grow up to 4
meters (13') long and weigh up to 200 kgs (440lbs). Gator gars are so
called because of their reptilian appearance and long jaws, armed with a
double row of sharp teeth. They are voracious ambush predators and have
been known to bite humans on occasion, although no confirmed deaths due
to alligator gars have been recorded to date. Gars are among the oldest
fish alive today; their origins can be traced back to the Cretaceous
period.
4 Sawfish
This critically endangered animal is a survivor from the Cretaceous
period, and can be found both in saltwater or in rivers and creeks, and
has been found up to 100 kms inland. Up to 7 meters (23') in length,
sawfish may look like sharks but are actually more closely related to
rays. Their “saw” is both a weapon and a sensory organ, covered on
electro-sensitive pores which allow it to sense prey despite its
terrible eyesight. Although usually peaceful, the sawfish can become
extremely dangerous if provoked. Due to an extraordinary fossil, we know
that gigantic, prehistoric sawfish were probably a staple food for the
largest carnivorous dinosaur, Spinosaurus, as a vertebra from the fish
was found stuck between the dinosaur’s teeth.
5 Arapaima
A close relative to the arowana (see #8), the Amazonian arapaima is
sometimes considered to be the largest freshwater fish in the world.
According to early descriptions, it could grow up to 4.5 meters (14' 8?)
long, but today, enormous individuals like these are seldom found and
most adult arapaimas average 2 meters (6' 6?) long. These slow moving
predators feed on smaller fish, crustaceans and whatever small animal
they can fit in their mouth. An interesting trait of this fish is that
it needs to breath oxygen from the air, like a cetacean, in order to
survive. Arapaimas pose no danger to humans and are often hunted for
their meat; unfortunately, they are very scarce nowadays. Although the
arapaima seemingly appeared in the Miocene period, it belongs to a much
older family, the Osteoglossidae, and therefore its origins can be
traced back to the age of dinosaurs.
6 Sturgeon
Another survivor from the age of dinosaurs (they were already around in
the early Jurassic), the sturgeon is well known for being one of the
main sources of caviar (which is made out of their roe or egg masses);
due to overfishing, these magnificent, armored fish are sadly endangered
nowadays. The largest sturgeon species can grow up to 6 meters (19' 7?)
long, being as large as most great white sharks; they feed on small
animals from the sea bottom and pose no danger to humans, unless
provoked (although they are so big that they have hurt, and even killed,
people unintentionally by leaping out of the water and landing on
boats!)
7 Frilled Shark
This deep sea predator, one of the most primitive sharks alive today, is
a relic from the Cretaceous period, when dinosaurs ruled the Earth.
Seldom seen alive, and only recently filmed for the first time, the
frilled shark can grow up to 2 meters (6' 6?) (with females being larger
than males) and they live in deep waters, where they feed mostly on
squid. They are not dangerous to humans, and as a matter of fact, most
frilled sharks spend their whole lives without seeing a human being.
Only dead or dying specimens are usually seen and recorded by fishermen
or scientists.
8 Arowana
Belonging to the ancient group of the Osteoglossids, these fish already
existed in the Jurassic period. Today, they are found in the Amazon, and
in parts of Africa, Asia and Australia. Sometimes kept as exotic pets,
arowanas are voracious predators that feed on any small animal they can
catch, including birds and bats which they catch in mid flight (they are
able to leap up to 2 meters (6' 6?) into the air). In China, arowanas
are known as “dragon-fish” due to their appearance, and they are thought
to be harbingers of good luck.
9 Lancetfish
The lancetfish has a very obvious “prehistoric” appearance, with those
fierce-looking, sharp teeth on its jaws and the sail on its back,
reminiscent of that of some dinosaurs (although, in the lancetfish the
sail is actually an enlarged dorsal fin). Even its scientific name has a
dinosaurian sound to it (Alepisaurus ferox). Up to two meters (6' 6?)
in length, this predator is found in all the oceans except for polar
regions; very voracious, it feeds on smaller fish and squid, and has
known to feed on members of its own species sometimes.
10 Hagfish
According to the fossil record, hagfish have existed for over 300
million years, which means they were already old when dinosaurs took
over the world! Found in relatively deep waters, these animals are
sometimes called slime eels, but they are not really eels, and actually,
they may not even be fish at all,according to some scientists. They are
very bizarre animals in all regards; they have a skull but lack a
spine, and they have two brains. Almost blind, they feed at night on the
carcasses of large animals (fish, cetaceans etc) which fall to the sea
bottom. They owe their “slime eel” nickname to the fact that they
produce a slimey substance to damage the gills of predatory fish; as a
result, they have virtually no natural enemies
Source :- http://worldtoptenthings.blogspot.in/2011/09/top-10-prehistoric-fish-alive-today.html
0 comments:
Post a Comment