Ocean lions are
altogether different from seals despite the fact that their appearance
is fundamentally the same as the stripped eye. In the first place, ocean
lions have two little external ears, while seals have no sound-related
shade. The other enormous contrast lies in the back folds. Ocean lions
can twist their back folds, this permits them to stroll without laying
their stomach on the ground. The seals, then again, slither on the
ground to move. The ocean lion, along these lines, is a creature
considerably more spry and adaptable than the seal. He is fit for
turning, hopping, bending his entire neck until he touches his back or
remains on the back flippers.
Ocean
lions have their bodies secured with hair to separate themselves from
the icy inside the water. Be that as it may, on the off chance that it
is excessively hot, you can evacuate both the pectoral and back blades
out of the water to keep up an appropriate temperature. The hide
transforms it twice per year and they help themselves from the three
nails they have on the rear blades to change it. Since they need to
chase inside the water, they have a decent view. During the evening, be
that as it may, they utilize the stubbles to get the vibrations of the
fish.
The distinction between male ocean lions and
females is extremely discernible, this is logically called sexual
dimorphism. The male can weigh around 150 kg more than the females. They
additionally have a more created mouth and a more greasy and beefy neck
to protect against the nibbles of alternate guys in the battles for
females. Concerning the sexual dimorphism of seals, I suggest you visit
the entrance focaswiki.com, a site gaining practical experience in these
staggering oceanic creatures where you can discover a great deal of
data.
This is the thing that the ocean lion coaches
enlighten us concerning in the instructive session that they give some
days at 12:30 in Aquarama. Parental figures prepare creatures through a
reward framework. Each time they do it right, they are sustained.
Furthermore, they utilize voice and hand signals for ocean lions to
perceive the activities. They are prepared from an early age, when they
start to ingest fish and take about a year to be superbly prepared.
Marine
mammals are a diverse group of approximately 130 species of mammals
that have adapted to life in the sea or depend on it for feeding. The term marine mammal does not designate an accurate taxonomic set. This
group includes cetaceans (whales, dolphins and porpoises), sirenians
(manatees and dugongs), pinnipedos (true seals, otarios and walruses)
and some otters (sea otter and sea cat). Polar bear, although not an aquatic animal, is also usually grouped
with marine mammals because it lives in sea ice for most or most of the
year and its high degree of adaptation to life at sea.
Marine
mammals acquired different traits to adapt to life at sea, such as a
generally larger size, hydrodynamic body shape, modified appendages and
experienced thermoregulatory adaptations. The different species, however, adapted to sea life in varying degrees. The most adapted are cetaceans and sirenians, whose life cycle runs
entirely in the water, while the other groups spend at least some time
on land.Although
marine mammals are a charismatic megafauna and supported by
environmental groups, many populations are vulnerable or endangered
because of a long history of commercial exploitation of oil, meat,
ivory, and skin . Most marine mammal species are protected from commercial exploitation.
Sirenians and
cetaceans are thought to descend from an ungulate ancestor, while
pinnipeds, otters, and polar bear come from a caniform ancestor. The morphological similarities between these diverse groups are the result of convergent and parallel evolutions.
Several groups of marine mammals of the past no longer exist today. In
addition to the ancestors of present whales or seals, there were the
Desmostylia, distant relatives of the manatees or the Kolponomos, a
genus of clams-eating sea bears, but not directly related to the modern
polar bear.
Adaptaciones
To develop their life at sea, marine mammals have developed important adaptations that resemble other marine animals. However there are big differences:
- Marine mammals breathe air, while most other marine animals draw oxygen from water.
- Marine mammals have hair. Cetaceans have little to no hair, usually very few bristles retained around the head or mouth. All
members of the order Carnivora have a coat of fur or hair, but it is
much thicker and more important for thermoregulation in sea otters and
polar bears than in pinnipeds. They do not have thick layers of hair because it would decrease their swimming capacity and the speed of movement in the water.
- Marine mammals have a thick layer of fat to isolate their bodies and prevent heat loss. Sea otters and polar bears are exceptions and rely more on their skin and behavior to prevent hypothermia.
- Marine mammals are viviparous. Most have a calf at each birth.
- Marine mammals feed on milk in their infancy. Maternal care is very important for the survival of offspring, which has to develop a thick layer of fat insulation. Milk from body fat in offspring.
- Marine mammals maintain high internal body temperature. Unlike most other oceanic animals, marine mammals maintain an internal temperature much higher than ambient temperature. The fat, the thick layer of skin, the air bubbles between skin and
water, are adaptations that help these animals in retaining body heat.
- Since
the mammals originally developed on land, their spine is optimized for
walking, so it moves with play from top to bottom but has less lateral
mobility. Because of this, marine mammals usually swim by moving their spine up and down. Conversely, fish usually swim by moving their spine laterally. For this reason, the fish usually have their vertical caudal fin, while the marine mammals have it horizontal.
- Marine
mammals that live exclusively in the sea (such as cetaceans) had to
undergo important adaptations in their sleep habits in order to be able
to sleep without drowning. From
studies of bottlenose dolphins in aquariums and zoos and also with
whales and dolphins released, it follows that they developed two methods
of sleep: either they remain static at two levels (vertically or
horizontally) or swim while sleeping in a similar state the nap.
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