Class MAMMALIA
ECOLOGICAL ROLE
Except for a few species that are top predators in their ecosystem, mammals are often preyed upon by many other organisms, including other mammals. They are an important food source to other organisms, and without mammals, ecosystems would collapse. Mammals are also an important economic resource for humans. Many mammals have been domesticated to provide humans with meat, milk, fibre, or kept as service animals or pets.
Except for a few species that are top predators in their ecosystem, mammals are often preyed upon by many other organisms, including other mammals. They are an important food source to other organisms, and without mammals, ecosystems would collapse. Mammals are also an important economic resource for humans. Many mammals have been domesticated to provide humans with meat, milk, fibre, or kept as service animals or pets.
MOVEMENT STRUCTURES/ TYPE
Mammals have skeletons with two main parts: a main axis (support) and limbs (appendages). They are quadrupedal, meaning they have four limbs that they walk on. Mammals move by contractile muscles that pull against attachment points in their rigid skeletons, causing the bones to move around specific joints. This muscle contraction directly affects the movement of the mammal as the muscle pulls in the direction the mammal wants the bones to move to. Certain mammals are able to crawl, walk, climb, run, jump, swim, gallop, glide and fly.
Mammals have skeletons with two main parts: a main axis (support) and limbs (appendages). They are quadrupedal, meaning they have four limbs that they walk on. Mammals move by contractile muscles that pull against attachment points in their rigid skeletons, causing the bones to move around specific joints. This muscle contraction directly affects the movement of the mammal as the muscle pulls in the direction the mammal wants the bones to move to. Certain mammals are able to crawl, walk, climb, run, jump, swim, gallop, glide and fly.
BODY COVERING; CELL LAYERS; LEVEL OF ORGANISATION; PROTECTION
Mammals have integumentary systems made up of three layers: the outermost epidermis, the dermis, and the hypodermis. This characteristic is not unique to mammals, but is found in all vertebrates. All mammals share at least three characteristics not found in other animals: Three middle ear bones, hair, and the production of milk by mammary glands. Other characteristics found in most mammals include a lower jaw made up of a single bone, differentiated teeth, four chambered hearts, a secondary palate separating air and food passages in the mouth, a muscular diaphragm separating thoracic and abdominal cavities, a highly developed brain, and separate sexes. Mammalian hair (or fur), made of a protein called keratin, is present in all mammals at some point in their development. This filamentous growth from the skin projects from the epidermis, although it grows from follicles deep in the dermis. The hair serves at least four functions, such as the providence of insulation, color patterning (to camouflage, warn predators, or to communicate social information), and aiding in sense of touch.
Mammals have integumentary systems made up of three layers: the outermost epidermis, the dermis, and the hypodermis. This characteristic is not unique to mammals, but is found in all vertebrates. All mammals share at least three characteristics not found in other animals: Three middle ear bones, hair, and the production of milk by mammary glands. Other characteristics found in most mammals include a lower jaw made up of a single bone, differentiated teeth, four chambered hearts, a secondary palate separating air and food passages in the mouth, a muscular diaphragm separating thoracic and abdominal cavities, a highly developed brain, and separate sexes. Mammalian hair (or fur), made of a protein called keratin, is present in all mammals at some point in their development. This filamentous growth from the skin projects from the epidermis, although it grows from follicles deep in the dermis. The hair serves at least four functions, such as the providence of insulation, color patterning (to camouflage, warn predators, or to communicate social information), and aiding in sense of touch.
SUPPORT
Mammals are vertebrates, meaning they have an internal bony support structure to which muscles and ligaments are attached. The mammalian skeletal structure consists of a head at one end of a vertebral column, from which ribs extend to support the organs and four limbs for locomotion. The vertebral column begins with a skull and ends in a tail, although some species lack a tail. The mammalian vertebrate can be split into five distinct regions of the spine: the cervical, thoracic, lumbar, sacral and caudal regions.
Mammals are vertebrates, meaning they have an internal bony support structure to which muscles and ligaments are attached. The mammalian skeletal structure consists of a head at one end of a vertebral column, from which ribs extend to support the organs and four limbs for locomotion. The vertebral column begins with a skull and ends in a tail, although some species lack a tail. The mammalian vertebrate can be split into five distinct regions of the spine: the cervical, thoracic, lumbar, sacral and caudal regions.
OBTAINING NUTRIENTS
Mammals can be herbivores, carnivores or omnivores. Once the mammalian has obtained food, they break down the food in the mouth through chewing, with the help of enzymes. The esophagus then transports the food to the stomach, where the food is broken down even further. The food then travels into the small intestine where digestion still continues with some nutrient absorption taking place. The food is passed along to the large intestine where the final absorption of nutrients takes place before the waste is transferred to the rectum.
Mammals can be herbivores, carnivores or omnivores. Once the mammalian has obtained food, they break down the food in the mouth through chewing, with the help of enzymes. The esophagus then transports the food to the stomach, where the food is broken down even further. The food then travels into the small intestine where digestion still continues with some nutrient absorption taking place. The food is passed along to the large intestine where the final absorption of nutrients takes place before the waste is transferred to the rectum.
RESPIRATION
Some mammals breathe through their nose, while others breathe through their mouths. As the air passes through the nose to the trachea, small microscopic hairs filter the air by attracting dust and microbes, that could cause damage or infection to the lungs. As the air passes through the airways it enters the lungs. The diaphragm and intercostal muscles between the ribs are the primary muscles of breathing. Mammals have two lungs that split by an airway called the bronchi. The air then moves to smaller airways called bronchioles. The bronchioles take the air to alveoli, which are small sacs in which gas exchange occurs. The oxygen diffuses from the alveoli into the blood and the carbon dioxide produced by cells as a waste product, will diffuse from the blood into alveoli to be exhaled.
Some mammals breathe through their nose, while others breathe through their mouths. As the air passes through the nose to the trachea, small microscopic hairs filter the air by attracting dust and microbes, that could cause damage or infection to the lungs. As the air passes through the airways it enters the lungs. The diaphragm and intercostal muscles between the ribs are the primary muscles of breathing. Mammals have two lungs that split by an airway called the bronchi. The air then moves to smaller airways called bronchioles. The bronchioles take the air to alveoli, which are small sacs in which gas exchange occurs. The oxygen diffuses from the alveoli into the blood and the carbon dioxide produced by cells as a waste product, will diffuse from the blood into alveoli to be exhaled.
CIRCULATION
Nearly all mammals are endothermic (warm blooded). They have a four chambered heart and shows double circulation. The aorta (artery arising from the left ventricle) takes the oxygenated blood to the body organs through a number of arteries. From these organs, the deoxygenated blood is collected by the vena cava and back to the right auricle. The right auricle pumps the deoxygenated blood into the right ventricle. The deoxygenated blood from the right ventricle is take by the pulmonary artery to the lungs for oxygenation. The oxygenated blood is returned to the left auricle of the heart by the pulmonary vein. From the left auricle, the blood flows to the left ventricle.
Nearly all mammals are endothermic (warm blooded). They have a four chambered heart and shows double circulation. The aorta (artery arising from the left ventricle) takes the oxygenated blood to the body organs through a number of arteries. From these organs, the deoxygenated blood is collected by the vena cava and back to the right auricle. The right auricle pumps the deoxygenated blood into the right ventricle. The deoxygenated blood from the right ventricle is take by the pulmonary artery to the lungs for oxygenation. The oxygenated blood is returned to the left auricle of the heart by the pulmonary vein. From the left auricle, the blood flows to the left ventricle.
EXCRETION
Most mammals have a similar digestive tract to humans. In mammals, excretion is the formation of urine in the kidneys, that is excreted by urination, and food waste is expelled through the anus. The skin also contains excretory functions. The skin eliminates wastes like urea and lactic acid through sweating.
Most mammals have a similar digestive tract to humans. In mammals, excretion is the formation of urine in the kidneys, that is excreted by urination, and food waste is expelled through the anus. The skin also contains excretory functions. The skin eliminates wastes like urea and lactic acid through sweating.
RESPONSE
Mammals have a highly developed brain, nerves and sensory organs such as eyes, nose, mouth, ears and sense of touch. Typically, mammalian hearing is well-developed and in some species, is the primary form of perception. For example, some mammals use echolocation to perceive objects in their environment, by listening to echoes from sounds generated by an animal. Most mammals have well-developed vocal cords and can communicate with one another using heterospecific sound. Vocal communication is used in a variety of social contexts, such as mating calls and warning calls. Mammals perceive their environment through tactile input to the hair and skin. Specialized hairs, whiskers or vibrissae have a sensory function, letting the animal know when it is in contact with an object in its environment. The skin is also an important sensory organ. Certain sections of the skin are especially sensitive to tactile stimuli. Vision is well-developed in a large number of mammals, and is important in nearly all aspects mammalian behaviour and ecology. All mammalian brains possess a neocortex (or neopallium) that is involved in higher functions, such as sensory perception, generation of motor commands, spatial reasoning, and in humans, language and conscious thought.
Mammals have a highly developed brain, nerves and sensory organs such as eyes, nose, mouth, ears and sense of touch. Typically, mammalian hearing is well-developed and in some species, is the primary form of perception. For example, some mammals use echolocation to perceive objects in their environment, by listening to echoes from sounds generated by an animal. Most mammals have well-developed vocal cords and can communicate with one another using heterospecific sound. Vocal communication is used in a variety of social contexts, such as mating calls and warning calls. Mammals perceive their environment through tactile input to the hair and skin. Specialized hairs, whiskers or vibrissae have a sensory function, letting the animal know when it is in contact with an object in its environment. The skin is also an important sensory organ. Certain sections of the skin are especially sensitive to tactile stimuli. Vision is well-developed in a large number of mammals, and is important in nearly all aspects mammalian behaviour and ecology. All mammalian brains possess a neocortex (or neopallium) that is involved in higher functions, such as sensory perception, generation of motor commands, spatial reasoning, and in humans, language and conscious thought.
REPRODUCTION
Most mammals, except monotremes and marsupials, are placental mammals. Mammals reproduce sexually through internal fertilization. With a few exceptions, mammals give birth to live young. Placental mammals are born in a more advanced state than non-placental mammals. The embryo is able to stay inside the mother because of the placenta, which allows nutrients to travel from the mother’s system to the embryo’s. All female mammals produce milk from their mammary glands in order to nourish their newborn offspring. This results in female and even male mammals to provide care for their young long after birth.
Most mammals, except monotremes and marsupials, are placental mammals. Mammals reproduce sexually through internal fertilization. With a few exceptions, mammals give birth to live young. Placental mammals are born in a more advanced state than non-placental mammals. The embryo is able to stay inside the mother because of the placenta, which allows nutrients to travel from the mother’s system to the embryo’s. All female mammals produce milk from their mammary glands in order to nourish their newborn offspring. This results in female and even male mammals to provide care for their young long after birth.