CachHayNhat - Whales are mammals, however, because they live in the ocean, these large animals are called marine mammals. In fact, the blue whale is the largest living mammal on this earth.
In terms of size, blue whales can grow to over 90ft (27m) in length and weigh over 150 tons. For comparison with the blue whale, the smallest known mammal in the world is the wasp bat, which is 1-1.5 inches long and weighs only 2 grams. Just like land mammals, whales possess a number of characteristics that are essential among many different mammals.
Some of these factors include:
Air Breathing - Mammals have lungs and need air to breathe, so they cannot breathe underwater like fish and amphibians
Milk Production - Mammals breastfeed and feed them nutrient-rich/fat milk for the first part of their lives until they are able to consume solid foods on their own.
Warm-blooded - Mammals are warm-blooded animals that get their energy by consuming food regularly. To protect themselves from the cold, most mammals develop a layer of fat, down, and/or hair that helps them provide extra calories during times of food shortages and helps keep vital organs alive. Theirs are not frozen.
Childbirth - Mammals carry an internal pregnancy and provide nutrients to their offspring through the umbilical cord until the child is born. Most non-mammalian animals lay eggs rather than give birth.
Note: While most mammals give birth there are a few exceptions such as the platypus and echidna which are also mammals but are known to lay eggs. Overall, there are more than 5,000 known species of mammals alive today.
Why are whales mammals?
Believe it or not, the earliest known ancestors of whales were terrestrial mammals. Over millions of years, whales have gradually evolved from terrestrial to oceanic, which helps explain why whales are warm-blooded, spawn there, and need air to survive rather than be born. with qualities similar to fish and amphibians. In fact, the whale's skeletal structure still bears signs of its land-dwelling past.
For example, bones in the whale's fins suggest the existence of limbs that are thought to have been used for hunting, survival and traveling on land rather than swimming in water. Close examination of their fin bones seems to suggest that individual digits may have helped their ancestors walk, retrieve objects, and fight.
Similar designs of mammals can also be seen on the backs of whales. The vertical movement of the spine suggests that the body is more likely to be used for running on land than swimming in the sea. This is a direct comparison to the skeletal structure of fish, which historically appear to have been developed primarily for swimming.
When observing the difference in swimming patterns between whales and fish, this point is more clearly illustrated. When a whale swims in water, it propels itself by bouncing its back up and down while using its fluke segments to move forward.
On the other hand, fish and sharks move from left to right to move through the water. In addition to whales, several other animals are considered marine mammals.
These animals include:
Dolphin
Porpoises
Stamp
walrus
When it comes to whales of the cetacean family, dolphins and porpoises are considered part of this group because they share many of the same physiological and evolutionary characteristics. The cetacean family does not include marine mammals such as seals and walruses.
In summary, both land mammals and marine mammals share a number of features that are necessary to be considered mammals.
Some of these features include:
Born a warm-blooded animal
Breastfeeding with milk
Carrying babies in the womb (mammals have a gestation period or gestation period can vary between different species)
Has lungs (mammals breathe air with lungs, not gills)
Possession of body hair (not all animals have body hair, and some animals such as whales may lose body hair shortly after birth.
How are fish different from whales?
Although they are both animals and live in the same ocean, there are many differences between aquatic animals like fish and marine mammals like whales. First, fish have gills that allow them to take in oxygen through the water by means of gas exchange.
To draw in oxygen, fish pull water into their mouths and run water through their gills to draw oxygen from the water. The oxygen is then distributed through the fish's blood to its vital organs. Depending on the species, blood may flow upstream to maximize oxygen use.
Another major difference between fish and mammals is that fish lay eggs rather than carrying young in the womb. For aquatic animals like fish, this is an important part of their survival because fish can lay hundreds or thousands of eggs in a signal year, and because marine mammals like whales can consume large amounts of fish daily so fish need to be able to produce enough offspring to continue to thrive in the ocean.
If fish give birth to their own offspring and carry offspring within them, they won't be able to produce nearly enough offspring to pass on their genes. While many factors distinguish fish from marine mammals, we will give you one more example of the stark difference between these two types of animals.
Unlike whales, fish are mostly cold-blooded animals. Being cold-blooded, the fish allows fish to adjust to the temperature of the outside environment instead of growing body fat and eating large amounts of calories to keep themselves warm. This allows the fish to consume fewer calories to survive, and the lack of body fat/fat body allows them to stay slim and remain extremely mobile in the water.
More information about mammals
Mammals can vary considerably in size, from 1 inch (bumblebee bats) to over 90 feet long and 150 tons in weight (blue whales).
With the exception of the monotreme (which lays eggs), almost all mammals give birth.
Mammals are warm-blooded and have developed or burgundy body fat to hunt and survive in cold regions where they would otherwise be able to live.
Some mammals have evolved over millennia from tetrapods to bipeds, and some species like whales have evolved flippers and flukes to survive in the ocean.
Most mammals generate steady body heat, burn energy, and require them to eat nutrient-rich foods containing essential fats and proteins regularly to maintain fat and heat levels. inside the body.
Some mammals such as humpback whales will eat large amounts of food during their feeding season and subsist on energy and fat by fasting during their mating season.
Humans and other animals are also known to develop layers of fat to provide extra calories and energy during times of food scarcity.
There are about 5,500 species of mammals recorded to date (as of 2011) and the list keeps growing!
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