Publisher's Synopsis
A Marine mammal is a mammal that has adapted to aquatic life and rely's on the ocean to maintain a healthy, livable existence. These amazing animals can be found living in all of the world's major oceans from the tropical environments in and around the equator to the northern and southern polar hemispheres in and around the Arctic and Antarctic oceans. Marine mammals share several characteristics that are common among all mammals such as the need to breathe air, being warm-blooded, having mammary glands which produce milk to feed their young, giving birth to live young (pregnancy/gestation periods) and in some cases having hair. Marine mammal adaptation to an aquatic lifestyle vary considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. While land mammals are similar in many ways marine mammals have adapted to deal with living in environments that are generally surrounded by water rather than being elusively surrounded by land, and way marine mammals live, hunt for food and navigate the world is largely dependent upon their oceanic environment and physical characteristics. For example marine mammals such as whales, dolphins and porpoises have streamlined bodies designed to reduce water resistance when swimming, they also have specialized lungs and muscles designed to store oxygen, thick blubber or fat to help maintain body heat in cold environments, large veins to help transfer blood to vital organs in a cold water or when in deep waters where compression can become an issue and fins, flukes, and flippers to assist with swimming. Other species such as polar bears have thick layers of fat and fur to help them maintain their body heat in cold climates, a large body to help keep them warm and disperse their body heat, thick curved claws for gripping the ice and predators, sharp teeth and strong jaws for tearing apart prey and powerful muscles for fighting and attacking. Seals have thick layers of fat/blubber to help keep them warm, rounded bodies to help disperse their body heat, limbs designed for walking/waddling on land with webbed feet/flippers to help them swim and teeth which they use to grip onto their prey. Seals, sea lions and walruses have a number of characteristics that are similar among the separate species but also share a few distinct differences as well. Marine Mammal Biology- An Evolutionary Approach presents rigorous and innovative research into the ecology and population biology of marine mammals. It compiles research articles and papers related to marine mammals including aspects of husbandry; behavior; conservation; veterinary medicine; anatomy; physiology; training; population trends; and the effects of pollution, climate change, and noise. A Marine mammal is a mammal that has adapted to aquatic life and rely's on the ocean to maintain a healthy, livable existence. These amazing animals can be found living in all of the world's major oceans from the tropical environments in and around the equator to the northern and southern polar hemispheres in and around the Arctic and Antarctic oceans. Marine mammals share several characteristics that are common among all mammals such as the need to breathe air, being warm-blooded, having mammary glands which produce milk to feed their young, giving birth to live young (pregnancy/gestation periods) and in some cases having hair. Marine mammal adaptation to an aquatic lifestyle vary considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. While land mammals are similar in many ways marine mammals have adapted to deal with living in environments that are generally surrounded by water rather than being elusively surrounded by land, and way marine mammals live, hunt for food and navigate the world is largely dependent upon their oceanic environment and physical characteristics. For example marine mammals such as whales, dolphins and porpoises have streamlined bodies designed to reduce water resistance when swimming, they also have specialized lungs and muscles designed to store oxygen, thick blubber or fat to help maintain body heat in cold environments, large veins to help transfer blood to vital organs in a cold water or when in deep waters where compression can become an issue and fins, flukes, and flippers to assist with swimming. Other species such as polar bears have thick layers of fat and fur to help them maintain their body heat in cold climates, a large body to help keep them warm and disperse their body heat, thick curved claws for gripping the ice and predators, sharp teeth and strong jaws for tearing apart prey and powerful muscles for fighting and attacking. Seals have thick layers of fat/blubber to help keep them warm, rounded bodies to help disperse their body heat, limbs designed for walking/waddling on land with webbed feet/flippers to help them swim and teeth which they use to grip onto their prey. Seals, sea lions and walruses have a number of characteristics that are similar among the separate species but also share a few distinct differences as well. Marine Mammal Biology- An Evolutionary Approach presents rigorous and innovative research into the ecology and population biology of marine mammals. It compiles research articles and papers related to marine mammals including aspects of husbandry; behavior; conservation; veterinary medicine; anatomy; physiology; training; population trends; and the effects of pollution, climate change, and noise. A Marine mammal is a mammal that has adapted to aquatic life and rely's on the ocean to maintain a healthy, livable existence. These amazing animals can be found living in all of the world's major oceans from the tropical environments in and around the equator to the northern and southern polar hemispheres in and around the Arctic and Antarctic oceans. Marine mammals share several characteristics that are common among all mammals such as the need to breathe air, being warm-blooded, having mammary glands which produce milk to feed their young, giving birth to live young (pregnancy/gestation periods) and in some cases having hair. Marine mammal adaptation to an aquatic lifestyle vary considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. While land mammals are similar in many ways marine mammals have adapted to deal with living in environments that are generally surrounded by water rather than being elusively surrounded by land, and way marine mammals live, hunt for food and navigate the world is largely dependent upon their oceanic environment and physical characteristics. For example marine mammals such as whales, dolphins and porpoises have streamlined bodies designed to reduce water resistance when swimming, they also have specialized lungs and muscles designed to store oxygen, thick blubber or fat to help maintain body heat in cold environments, large veins to help transfer blood to vital organs in a cold water or when in deep waters where compression can become an issue and fins, flukes, and flippers to assist with swimming. Other species such as polar bears have thick layers of fat and fur to help them maintain their body heat in cold climates, a large body to help keep them warm and disperse their body heat, thick curved claws for gripping the ice and predators, sharp teeth and strong jaws for tearing apart prey and powerful muscles for fighting and attacking. Seals have thick layers of fat/blubber to help keep them warm, rounded bodies to help disperse their body heat, limbs designed for wa