Hybrids between different species within the same genus such as between lions and tigers are known as interspecific hybrids or crosses. When endothermy first appeared in the evolution of mammals is uncertain, though it is generally agreed to have first evolved in non-mammalian therapsids. International Union for Conservation of Nature. Data on various human impacts marine vessels, fishing activity, debris are also collected. Since their invention in the s plastics have been polluting our oceans and waterways.
Form and function
Dog otters are known to kill and eat other young males. Territorial behaviour in otters helps to control population density by spacing out individuals. It also avoids over-exploitation of food resources. HOLTS Otters rest in underground dens, called holts, under waterside trees or in old rabbit burrows or in cavities in bank-side rocks. They can be up to 10 meters underground and may have underwater entrances.
Mature trees, particularly those with well-developed root systems, leaning trunks and overhanging branches provide ideal holt sites. Ash trees and sycamore trees are important sites for otter holts as both have shallow spreading roots which make ideal roofs for holts. COUCHES Otters also use above-ground resting places, called couches, built on the banks of a river, stream or lake, and occasionally further inland, often in thick vegetation or reed beds.
Rolling places, where the otter dries and grooms its fur after leaving the water, may also be used as couches. Much of their time is spent hunting, travelling and patrolling their territory. Its diet consists primarily of fish, but may also include frogs, crustaceans, molluscs, birds and even small mammals. In winter, as the water in streams, rivers and lakes cools, cold-blooded fish slow down and become easier to catch; eels bury themselves in mud, and are dug out and caught.
In spring, as the waters warm and fish become more active and difficult to catch, the otter hunts for frogs, crustaceans, and young waterfowl in unguarded nests. Analysis of fish bones in spraints suggests eels are a main component of diet.
Otters may seasonally move to headwaters and upland marshes to hunt for spawning frogs and may follow runs of salmon and sea-trout upstream. Coarse fish such as roach, perch, pike, bream, rudd, and tench are also taken, and otters living near the sea hunt for crabs and for bottom-dwelling fish such as flounder, butterfish, and pollack.
After swimming, it dries itself by rolling on the ground and rubbing against logs or vegetation. It uses its teeth and claws to remove dirt and debris from its fur and smears oil from sebaceous glands onto the fur to retain the waterproof barrier of its outer coat.
Grooming may also remove parasites. Coat maintenance is such an important factor that coastal dwelling otters must have a source of freshwater nearby; this may then influence habitat selection and distribution. BREEDING Otters are largely solitary with males and females having close contact only for courting and mating, the male playing no part in rearing the resultant cubs.
From captive breeding and zoo animals, breeding can occur throughout the year but it is not known if this is generally the case in the wild. There would be an advantage in timing birth to the start of the most productive seasons of the year.
It is thought otter bitches can breed once every two years. After nine weeks of gestation, the bitch gives birth in a secure holt lined with grass, reeds, twigs and other vegetation.
Litter size ranges from one to five cubs, but two or three are the norm. The cubs are born blind and helpless but fully furred. At seven weeks the cubs begin to take solid food and by three months they are weaned but still dependent on their mother to catch their food.
From four months of age, the cubs accompany their mother on hunting expeditions and learn fish. They stay with her for about a year, during which time contact is very close. Eventually, at around 12 months, the family splits up and the bitch begins her reproductive cycle again. It feeds and moves on. This urge to wander prevents overcrowding and overfishing in any particular pool or stretch of the river. Dog otters and bitches with cubs keep to their own separate territories which they defend aggressively.
Adults have close contact only when courting and mating. When fresh spraints of a territory-holding otter are encountered by an intruder, they serve as a warning: Being solitary animals and stealth hunters, otters tend not to vocal communications and are generally silent. Nevertheless, several different calls are used for short-distance communication.
Otters without a territory include yearling cubs who have recently separated from their mothers, and unmated adolescent males and females of two to three years. These homeless individuals live a transient existence, often in sub-optimal habitats. Otter spraint is sometimes found on the high moors which otters may use to get from one river catchment to another; Cranmere Pool on Dartmoor is close to the watersheds of three main rivers, the Dart, the Taw and the Okement.
During their wanderings, young otters gain strength and experience, search for and explore new habitats, check scent marks, test territory boundaries and eventually, if they survive, establish their own territory.
For otters to spread into new areas, it is suggested that males are highly itinerant, and it is only after females have set up home ranges that breeding takes place and a population becomes established.
Otters are not able to breed until they are around two years old and cubs stay with their mother for up to 18 months, so a bitch is unlikely to rear more than two litters in her lifetime. When cubs leave their mother they are at their most vulnerable and the mortality rate is highest at this time.
The short life expectancy of wild otters combined with late sexual maturity result in slow population growth. Whilst many threats facing otter populations are well known, the full explanation for this short lifespan is not fully understood.
Post mortem studies which necessarily have analysed only those carcasses recovered, so to some extent represent a biased sample suggested traffic deaths are a key mortality factor, and that there are peak periods for these, namely winter, when river levels are high, forcing otters to cross over, instead of under, bridges.
An additional mortality factor appeared to be injuries from direct aggression between individuals, which might be associated with territorial behaviour. Regular recent surveys suggest that from eight to eleven otters customarily live in the Axe catchment. The Dart is an otter stronghold, with territories believed to cover its entire length.
Otters are found along the main river and on its tributaries. In summer , Devon Mammal Group and Devon Wildlife Trust surveyed the city of Exeter and found more than otter signs right through the heart of the city along the River Exe and the canals. The River Otter starts its south-westerly journey to the sea from across the county border in Somerset. After decades of decline, otters have made a good comeback on the river.
The settlements Ottery St Mary and Otterton may be named after the river rather than the mammal, though the etymologies are probably linked, a factor not overlooked by the local Otter Brewery. The River Plym rises on Dartmoor and flows south to Plymouth. Previously isolated otter populations are now breeding successfully on the Plym. The River Tamar is 50 miles long and is a natural boundary between Devon and Cornwall.
Otters frequent the whole length of the river. The Museum of Barnstaple and North Devon has a special room devoted to Tarka, which is well worth a visit. Otter numbers are increasing along this beautiful river. Otter signs are infrequently found around the urban areas of Newton Abbot, where the river is joined by the rivers Lemon, Bovey, and Aller, emptying into the Teign Estuary.
The Torridge catchment supports one of the best otter populations in England. Scientists who spend years studying the otter seldom see one in the wild. Otters are nocturnal, nomadic, semi-aquatic and secretive. Their finely tuned senses mean that they almost certainly will be aware of your presence before you see them, and they will be gone.
You may not be lucky enough to see a wild otter but the following accessible areas, where otters are known to visit, are good places to look for field signs of otter activity. Beam Weir is frequently visited by otters. Above the weir, a footpath and cycle trail crosses the River Torridge three times in less than half a mile, each bridge giving good views of typical otter habitat. Buried in a steep-sided, wooded valley, the reserve overlooks the River Torridge. It is a Site of Special Scientific Interest comprising 57 hectares of deciduous river valley woodland, riverside meadows, marsh and river.
Otters are sometimes seen from a hide overlooking the river. Totnes Weir on the River Dart separates the freshwater from the tidal stretch of the river that winds down to the sea at Dartmouth. The sandbank below the weir is a gathering place for gulls, geese and wildfowl. Alongside the weir is a salmon ladder, fished by heron, and the weir pool is visited by migrating sea trout. Otters have been spotted along the banks of the river and spraints can often be found.
Slapton Ley, which includes a large natural lake separated from the sea by a narrow shingle bar, is a National Nature Reserve and Site of Special Scientific Interest. Blood flows nearly continuously back into the atrium, which acts as the receiving chamber, and from here through an opening into the left ventricle.
Most blood flows passively into the heart while both the atria and ventricles are relaxed, but toward the end of the ventricular relaxation period , the left atrium will contract, pumping blood into the ventricle. The heart also requires nutrients and oxygen found in blood like other muscles, and is supplied via coronary arteries. The integumentary system is made up of three layers: The epidermis is typically 10 to 30 cells thick; its main function is to provide a waterproof layer.
Its outermost cells are constantly lost; its bottommost cells are constantly dividing and pushing upward. The middle layer, the dermis, is 15 to 40 times thicker than the epidermis. The dermis is made up of many components, such as bony structures and blood vessels. The hypodermis is made up of adipose tissue , which stores lipids and provides cushioning and insulation. The thickness of this layer varies widely from species to species; : It is a definitive characteristic of the class.
Though some mammals have very little, careful examination reveals the characteristic, often in obscure parts of their bodies. Herbivores have developed a diverse range of physical structures to facilitate the consumption of plant material. To break up intact plant tissues, mammals have developed teeth structures that reflect their feeding preferences. For instance, frugivores animals that feed primarily on fruit and herbivores that feed on soft foliage have low-crowned teeth specialized for grinding foliage and seeds.
Grazing animals that tend to eat hard, silica -rich grasses, have high-crowned teeth, which are capable of grinding tough plant tissues and do not wear down as quickly as low-crowned teeth.
The stomach of Artiodactyls is divided into four sections: After the plant material is consumed, it is mixed with saliva in the rumen and reticulum and separates into solid and liquid material. The solids lump together to form a bolus or cud , and is regurgitated. When the bolus enters the mouth, the fluid is squeezed out with the tongue and swallowed again.
Ingested food passes to the rumen and reticulum where cellulytic microbes bacteria , protozoa and fungi produce cellulase , which is needed to break down the cellulose in plants. The caecum is either absent or short and simple, and the large intestine is not sacculated or much wider than the small intestine.
The mammalian excretory system involves many components. Like most other land animals, mammals are ureotelic , and convert ammonia into urea , which is done by the liver as part of the urea cycle.
Only the mammalian kidney has a bean shape, although there are some exceptions, such as the multilobed reniculate kidneys of pinnipeds, cetaceans and bears. In the embryo, the embryonic cloaca divides into a posterior region that becomes part of the anus, and an anterior region that has different fates depending on the sex of the individual: As in all other tetrapods, mammals have a larynx that can quickly open and close to produce sounds, and a supralaryngeal vocal tract which filters this sound.
The lungs and surrounding musculature provide the air stream and pressure required to phonate. The larynx controls the pitch and volume of sound, but the strength the lungs exert to exhale also contributes to volume. More primitive mammals, such as the echidna, can only hiss, as sound is achieved solely through exhaling through a partially closed larynx. Other mammals phonate using vocal folds , as opposed to the vocal cords seen in birds and reptiles. The movement or tenseness of the vocal folds can result in many sounds such as purring and screaming.
Mammals can change the position of the larynx, allowing them to breathe through the nose while swallowing through the mouth, and to form both oral and nasal sounds; nasal sounds, such as a dog whine, are generally soft sounds, and oral sounds, such as a dog bark, are generally loud.
Some mammals have a large larynx and thus a low-pitched voice, namely the hammer-headed bat Hypsignathus monstrosus where the larynx can take up the entirety of the thoracic cavity while pushing the lungs, heart, and trachea into the abdomen.
Ultrasound is inaudible to birds and reptiles, which might have been important during the Mesozoic, when birds and reptiles were the dominant predators. This private channel is used by some rodents in, for example, mother-to-pup communication, and by bats when echolocating. Toothed whales also use echolocation, but, as opposed to the vocal membrane that extends upward from the vocal folds, they have a melon to manipulate sounds.
Some mammals, namely the primates, have air sacs attached to the larynx, which may function to lower the resonances or increase the volume of sound. The vocal production system is controlled by the cranial nerve nuclei in the brain, and supplied by the recurrent laryngeal nerve and the superior laryngeal nerve , branches of the vagus nerve.
The vocal tract is supplied by the hypoglossal nerve and facial nerves. Electrical stimulation of the periaqueductal gray PEG region of the mammalian midbrain elicit vocalizations. The ability to learn new vocalizations is only exemplified in humans, seals, cetaceans, elephants and possibly bats; in humans, this is the result of a direct connection between the motor cortex , which controls movement, and the motor neurons in the spinal cord.
The fur of mammals has many uses protection, sensory purposes, waterproofing, and camouflage, with the primary usage being thermoregulation. Mammalian coats are colored for a variety of reasons, the major selective pressures including camouflage , sexual selection , communication and physiological processes such as temperature regulation. Camouflage is a powerful influence in a large number of mammals, as it helps to conceal individuals from predators or prey. Mammals with a darker colored coat can absorb more heat from solar radiation, and stay warmer, and some smaller mammals, such as voles , have darker fur in the winter.
The white, pigmentless fur of arctic mammals, such as the polar bear, may reflect more solar radiation directly onto the skin. The ancestral condition for mammal reproduction is the birthing of relatively undeveloped, either through direct vivipary or a short period as soft-shelled eggs.
This is likely due to the fact that the torso could not expand due to the presence of epipubic bones. The oldest demonstration of this reproductive style is with Kayentatherium , which produced undeveloped perinates , but at much higher litter sizes than any modern mammal, 38 specimens.
In male placentals, the penis is used both for urination and copulation. Depending on the species, an erection may be fueled by blood flow into vascular, spongy tissue or by muscular action. A penis may be contained in a sheath when not erect, and some placentals also have a penis bone baculum. Marsupials typically have forked penises while the monotreme penis generally has four heads with only two functioning. The testes of most mammals descend into the scrotum which is typically posterior to the penis but is often anterior in marsupials.
Female mammals generally have a clitoris , labia majora and labia minora on the outside, while the internal system contains paired oviducts , uteri , cervices and a vagina. Marsupials have two lateral vaginas and a medial vagina. The "vagina" of monotremes is better understood as a "urogenital sinus". The uterine systems of placental mammals can vary between a duplex, were there are two uteri and cervices which open into the vagina, a bipartite, were two uterine horns have a single cervix that connects to the vagina, a bicornuate, which consists where two uterine horns that are connected distally but separate medially creating a Y-shape, and a simplex, which has a single uterus.
Most mammals are viviparous , giving birth to live young. However, the five species of monotreme, the platypus and the four species of echidna, lay eggs. The monotremes have a sex determination system different from that of most other mammals. Viviparous mammals are in the subclass Theria; those living today are in the marsupial and placental infraclasses.
Marsupials have a short gestation period, typically shorter than its estrous cycle and gives birth to an undeveloped newborn that then undergoes further development; in many species, this takes place within a pouch-like sac, the marsupium , located in the front of the mother's abdomen.
This is the plesiomorphic condition among viviparous mammals; the presence of epipubic bones in all non-placental mammals prevents the expansion of the torso needed for full pregnancy.
The mammary glands of mammals are specialized to produce milk, the primary source of nutrition for newborns. The monotremes branched early from other mammals and do not have the nipples seen in most mammals, but they do have mammary glands. The young lick the milk from a mammary patch on the mother's belly.
Nearly all mammals are endothermic "warm-blooded". Most mammals also have hair to help keep them warm. Like birds, mammals can forage or hunt in weather and climates too cold for ectothermic "cold-blooded" reptiles and insects. Endothermy requires plenty of food energy, so mammals eat more food per unit of body weight than most reptiles. A rare exception, the naked mole-rat produces little metabolic heat, so it is considered an operational poikilotherm. Among mammals, species maximum lifespan varies significantly for example the shrew has a lifespan of two years, whereas the oldest bowhead whale is recorded to be years.
In a study by Hart and Setlow,  it was found that DNA excision repair capability increased systematically with species lifespan among seven mammalian species. Species lifespan was observed to be robustly correlated with the capacity to recognize DNA double-strand breaks as well as the level of the DNA repair protein Ku Most vertebrates—the amphibians, the reptiles and some mammals such as humans and bears—are plantigrade , walking on the whole of the underside of the foot.
Many mammals, such as cats and dogs, are digitigrade , walking on their toes, the greater stride length allowing more speed. Digitigrade mammals are also often adept at quiet movement. This even further increases their stride length and thus their speed. Giant anteaters  and platypuses  are also knuckle-walkers. Some mammals are bipeds , using only two limbs for locomotion, which can be seen in, for example, humans and the great apes.
Bipedal species have a larger field of vision than quadrupeds, conserve more energy and have the ability to manipulate objects with their hands, which aids in foraging. Instead of walking, some bipeds hop, such as kangaroos and kangaroo rats.
Animals will use different gaits for different speeds, terrain and situations. For example, horses show four natural gaits, the slowest horse gait is the walk , then there are three faster gaits which, from slowest to fastest, are the trot , the canter and the gallop. Animals may also have unusual gaits that are used occasionally, such as for moving sideways or backwards. For example, the main human gaits are bipedal walking and running , but they employ many other gaits occasionally, including a four-legged crawl in tight spaces.
Gaits can be grouped into categories according to their patterns of support sequence. For quadrupeds, there are three main categories: Running is considered to occur when at some points in the stride all feet are off the ground in a moment of suspension. Arboreal animals frequently have elongated limbs that help them cross gaps, reach fruit or other resources, test the firmness of support ahead and, in some cases, to brachiate swing between trees. In the spider monkey, the tip of the tail has either a bare patch or adhesive pad, which provides increased friction.
Claws can be used to interact with rough substrates and reorient the direction of forces the animal applies.
This is what allows squirrels to climb tree trunks that are so large to be essentially flat from the perspective of such a small animal. However, claws can interfere with an animal's ability to grasp very small branches, as they may wrap too far around and prick the animal's own paw.
Frictional gripping is used by primates, relying upon hairless fingertips. Squeezing the branch between the fingertips generates frictional force that holds the animal's hand to the branch. However, this type of grip depends upon the angle of the frictional force, thus upon the diameter of the branch, with larger branches resulting in reduced gripping ability. To control descent, especially down large diameter branches, some arboreal animals such as squirrels have evolved highly mobile ankle joints that permit rotating the foot into a 'reversed' posture.
This allows the claws to hook into the rough surface of the bark, opposing the force of gravity. Small size provides many advantages to arboreal species: Both pitching and tipping become irrelevant, as the only method of failure would be losing their grip.
Bats are the only mammals that can truly fly. They fly through the air at a constant speed by moving their wings up and down usually with some fore-aft movement as well.
Because the animal is in motion, there is some airflow relative to its body which, combined with the velocity of the wings, generates a faster airflow moving over the wing. This generates a lift force vector pointing forwards and upwards, and a drag force vector pointing rearwards and upwards. The upwards components of these counteract gravity, keeping the body in the air, while the forward component provides thrust to counteract both the drag from the wing and from the body as a whole.
The wings of bats are much thinner and consist of more bones than that of birds, allowing bats to maneuver more accurately and fly with more lift and less drag. These sensitive areas are different in bats, as each bump has a tiny hair in the center, making it even more sensitive and allowing the bat to detect and collect information about the air flowing over its wings, and to fly more efficiently by changing the shape of its wings in response.
Fossorial creatures live in subterranean environments. Many fossorial mammals were classified under the, now obsolete, order Insectivora , such as shrews, hedgehogs and moles. Fossorial mammals have a fusiform body, thickest at the shoulders and tapering off at the tail and nose. Unable to see in the dark burrows, most have degenerated eyes, but degeneration varies between species; pocket gophers , for example, are only semi-fossorial and have very small yet functional eyes, in the fully fossorial marsupial mole the eyes are degenerated and useless, talpa moles have vestigial eyes and the cape golden mole has a layer of skin covering the eyes.
External ears flaps are also very small or absent. Truly fossorial mammals have short, stout legs as strength is more important than speed to a burrowing mammal, but semi-fossorial mammals have cursorial legs.
The front paws are broad and have strong claws to help in loosening dirt while excavating burrows, and the back paws have webbing, as well as claws, which aids in throwing loosened dirt backwards. Most have large incisors to prevent dirt from flying into their mouth. Fully aquatic mammals, the cetaceans and sirenians , have lost their legs and have a tail fin to propel themselves through the water.
Flipper movement is continuous. Whales swim by moving their tail fin and lower body up and down, propelling themselves through vertical movement, while their flippers are mainly used for steering. Their skeletal anatomy allows them to be fast swimmers. Most species have a dorsal fin to prevent themselves from turning upside-down in the water.
The forelimbs are paddle-like flippers which aid in turning and slowing. Semi-aquatic mammals, like pinnipeds, have two pairs of flippers on the front and back, the fore-flippers and hind-flippers. The elbows and ankles are enclosed within the body. In addition to their streamlined bodies, they have smooth networks of muscle bundles in their skin that may increase laminar flow and make it easier for them to slip through water.
They also lack arrector pili , so their fur can be streamlined as they swim. Many mammals communicate by vocalizing. Vocal communication serves many purposes, including in mating rituals, as warning calls ,  to indicate food sources, and for social purposes.
Males often call during mating rituals to ward off other males and to attract females, as in the roaring of lions and red deer. For example, if an alarm call signals a python, the monkeys climb into the trees, whereas the eagle alarm causes monkeys to seek a hiding place on the ground.
Some of the rumbling calls are infrasonic , below the hearing range of humans, and can be heard by other elephants up to 6 miles 9. Mammals signal by a variety of means. Many give visual anti-predator signals , as when deer and gazelle stot , honestly indicating their fit condition and their ability to escape,   or when white-tailed deer and other prey mammals flag with conspicuous tail markings when alarmed, informing the predator that it has been detected.
To maintain a high constant body temperature is energy expensive — mammals therefore need a nutritious and plentiful diet. While the earliest mammals were probably predators, different species have since adapted to meet their dietary requirements in a variety of ways.
Some eat other animals — this is a carnivorous diet and includes insectivorous diets. Other mammals, called herbivores , eat plants, which contain complex carbohydrates such as cellulose. An herbivorous diet includes subtypes such as granivory seed eating , folivory leaf eating , frugivory fruit eating , nectarivory nectar eating , gummivory gum eating and mycophagy fungus eating.
The digestive tract of an herbivore is host to bacteria that ferment these complex substances, and make them available for digestion, which are either housed in the multichambered stomach or in a large cecum.
Carnivorous mammals have a simple digestive tract because the proteins , lipids and minerals found in meat require little in the way of specialized digestion.
Exceptions to this include baleen whales who also house gut flora in a multi-chambered stomach, like terrestrial herbivores. The size of an animal is also a factor in determining diet type Allen's rule. Since small mammals have a high ratio of heat-losing surface area to heat-generating volume, they tend to have high energy requirements and a high metabolic rate.
Larger animals, on the other hand, generate more heat and less of this heat is lost. They can therefore tolerate either a slower collection process carnivores that feed on larger vertebrates or a slower digestive process herbivores. The only large insectivorous mammals are those that feed on huge colonies of insects ants or termites.
Some mammals are omnivores and display varying degrees of carnivory and herbivory, generally leaning in favor of one more than the other. Since plants and meat are digested differently, there is a preference for one over the other, as in bears where some species may be mostly carnivorous and others mostly herbivorous. The dentition of hypocarnivores consists of dull, triangular carnassial teeth meant for grinding food.
Hypercarnivores, however, have conical teeth and sharp carnassials meant for slashing, and in some cases strong jaws for bone-crushing, as in the case of hyenas , allowing them to consume bones; some extinct groups, notably the Machairodontinae , had saber-shaped canines. Some physiological carnivores consume plant matter and some physiological herbivores consume meat.
From a behavioral aspect, this would make them omnivores, but from the physiological standpoint, this may be due to zoopharmacognosy. Physiologically, animals must be able to obtain both energy and nutrients from plant and animal materials to be considered omnivorous. Thus, such animals are still able to be classified as carnivores and herbivores when they are just obtaining nutrients from materials originating from sources that do not seemingly complement their classification. Many mammals, in the absence of sufficient food requirements in an environment, suppress their metabolism and conserve energy in a process known as hibernation.
In intelligent mammals, such as primates, the cerebrum is larger relative to the rest of the brain. Intelligence itself is not easy to define, but indications of intelligence include the ability to learn, matched with behavioral flexibility. Rats , for example, are considered to be highly intelligent, as they can learn and perform new tasks, an ability that may be important when they first colonize a fresh habitat.
In some mammals, food gathering appears to be related to intelligence: Tool use by animals may indicate different levels of learning and cognition. Brain size was previously considered a major indicator of the intelligence of an animal.
Since most of the brain is used for maintaining bodily functions, greater ratios of brain to body mass may increase the amount of brain mass available for more complex cognitive tasks. Comparison of a particular animal's brain size with the expected brain size based on such allometric analysis provides an encephalisation quotient that can be used as another indication of animal intelligence.
Self-awareness appears to be a sign of abstract thinking. Self-awareness, although not well-defined, is believed to be a precursor to more advanced processes such as metacognitive reasoning. The traditional method for measuring this is the mirror test , which determines if an animal possesses the ability of self-recognition.
Eusociality is the highest level of social organization. These societies have an overlap of adult generations, the division of reproductive labor and cooperative caring of young. Usually insects, such as bees , ants and termites, have eusocial behavior, but it is demonstrated in two rodent species: Presociality is when animals exhibit more than just sexual interactions with members of the same species, but fall short of qualifying as eusocial. That is, presocial animals can display communal living, cooperative care of young, or primitive division of reproductive labor, but they do not display all of the three essential traits of eusocial animals.
Humans and some species of Callitrichidae marmosets and tamarins are unique among primates in their degree of cooperative care of young. A fission-fusion society is a society that changes frequently in its size and composition, making up a permanent social group called the "parent group".
Also, I and others who work with children and adults with neurological disorders have seen them experience those symptoms when they drink long cooked bone broth. Those extremes will denature fragile protein molecules. Yes, bone broth and meat stock will help strengthen your bones, joints and ligaments, because they contain the building blocks your body needs to build and repair-gelatin and collagen. However, remember that neither is very high in minerals, though those that are contained in bone broth are in an electrolytic form, which makes them very easy for your body to utilize.
Bones need calcium, and calcium that the body can absorb. No other type of calcium can be utilized by the body…. Weight-bearing exercise is very important for strong bones.
One must take in calcium that the body can absorb raw dairy, cultured dairy such as yogurt, creme fraiche or kefir , and then drive it into the bones with weight-bearing exercise.
Hi Loren, Thank you for sharing your story. Yes, our bodies can have extreme reactions to glutamine. Glad you figured it out and things are better! My 16 mo old has all kinds of food allergies that result in severe red, itchy skin from the neck to the toes. Even despite all the eliminations his and mine , we are still weeding through.
My latest discovery is that he might also be HIT, histamine intolerant. As you probably know long cooked bone broth and all fermented foods are very high in histamine. Do you know if meat stock cooked as you recommend it is NOT high in histamine? Your assertion about the pressure cooker is incorrect. Also, my understanding is that protein starts to denature at degrees. Slow cookers, ovens and stove tops all denature proteins. The other dark side of bone broth is that the bones come from an animal that wanted to live but instead suffered horrible cruelty and was then brutally murdered.
Because science says they do. The only way to not have a negative impact on other living beings is to cease to live. Hi there Yes, vinegar is used in long cooked bone broth. It is not used in meat stock, because of the amount of meat in the pot. Vinegar acts on the bones, not the meat. Hi Clarissa Thank you for that; I will take a read. I prefer not to cook at high temperature and high pressure. I know our ancestors cooked meat and or bones, or whatever they were cooking slow and low.
Since bones are the manufacturers of blood, and since no bones are entirely clean of meat, the impurities are likely blood particles, etc. Skimming the scum makes for a cleaner broth or stock, if you will. Thank you for the information. I think my son has leaky gut.
Then what do they eat? Lots of veggies and most meat has large amounts of glutamic acid…seeds…You name it. Also, studies show it actually is protective from neurotoxicity…. I cook my chicken bone broth for about 4 hours at high pressure then 2 hrs at low in my electric pressure cooker.
I use chicken wings which break down quicker than chicken feet. My broth is beautifully gelatinous when cooled. Will this high-pressure method avoid the glutamic acid problem? I really have no idea. We have not done any tests on pressure cooked bone broth so I cannot say.
If I find out any info, I will surely post about it! Thank you for your message. I do not know if the short cooked meat stock is low in histamines, but I would think it would be. I know GAPS can be hard with those with histamine intolerance, but there are ways to implement it low-histamine. I would be happy to talk with you about it. If you would like to, I offer a complementary conversation on my Wellness Consultations page, http: I am not clear about your question…who are you referring to?
I do well on the meat broth and I really enjoy it. I have watched some people on you tube cooking bone broth and then pressure canning it for there pantry is that ok ,,,,,,And they use it for anything calling for beef broth is that ok. Negatives can perhaps be related to food handling and not obtaining clean bones to use for broth.
Food handling is crucial. Boiling to bring broth back up to a clean state is important after the broth has been refrigerated. Making sure the glass container used to store the broth is sterile is also something to be considered. The devil is in the details! So my daughter had brain cancer in and I would assume I should not be giving her bone broth then? Is meat broth still healthy and if so are there benefits?
If so can you tell me some of them? Would you suggest store bought, powdered collagen? Can you please provide the research that is the basis for your claims?
When I mentioned it to two different doctors, one laughed and the other told me it was all in my head. I know a ton of folks who are regularly drinking bone broth to actually heal the gut and have autoimmune issues. This is the staple food of the GAPS gut and psychology syndrome and I have never, ever heard of anything like this.
Is there any data? Do you have a source for these adverse events? Is this really a thing? My wife drinks this daily and we used to drink it several times a day when we were doing very strict GAPS. Yes, it is very important to bring bone broth back up to a boil after it has been refrigerated. Skim and discard any scum that rises to the top and then proceed with drinking or using in a recipe!
Thank you for your message and question. The study was done by Kim Schuette of Biodynamic Wellness. You can see the study here: The research about glutamic acid and its affect on brain function as an excitotoxin was done by Dr.
Russell Blaylock, a board certified neurosurgeon years ago. The Taste that Kills. Thank you for your message! I understand your confusion! Natasha Campbell-McBride has read, approved, and endorses my book on Meat Stock and Bone Broth—what they are, how to make them, and when they are used. My hope is that my work will help to inform those CGPs that took the training prior, so that they can start letting their patients know about Meat Stock and its role in the Intro Diet, which, according to Dr.
Natasha, is where all the healing and sealing happens. Also, in terms of glutamic acid and its affect on brain function as a neurotoxin or excitotoxin, it comes from the work of Dr. Russell Blaylock, a board-certified neurosurgeon who wrote on the issue in his book: We found out about the high levels of glutamic acid when batches of chicken broth long cooked bone broth—24 hours and short cooked broth—was sent to a lab for amino acid analysis.
You can find the original study here: It is my understanding that meat stock is best when dealing with brain issues—remember that the issue with bone broth is that broth that is cooked long —24 hours or more—will be high in glutamic acid. So, I would use short cooked meat stock for your daughter. Both bone broth and meat stock are chock full of benefits: Often, processed powders contain denatured molecules that can cause problems in the body.
I Googled this because I took powdered bone broth for about 2 months. It definitely helped my gut — I can even take aspirin now without hurting my stomach. However, I ended up having a mini stroke. Has anyone had anything like this? I have started using grass fed beef marrow bones in the instant pot under high pressure for 35 minutes.
It makes the most amazing bone broth. I let it cool, strain, bottle and left the fat cap form which I remove in one piece. It is delicious just the way it is, or for a soup base.
A friend just sent me this post. I had my son on the GAPS diet when he started having seizures- I had come across something about glutamic acid and it being a neurotoxin. I never could find out anything related to the use of stocks and broths, so this is enlightening. Also, I canned up some broth, which has to be at a real high temp. I was concerned about what that might do to the fat that is the stock, but now have concerns that the high heat used for canning also would increase the glutamic acid?
It would be great for you to add some meaty backs or a leg or two into your kits to make a meat stock. Then, bring it to a boil, skim and discard any scum, and put to a simmer with the lid on for about an hour and a half to 3 hours most.
This will make a really good—delicious and nutritious- meat stock, that is low in glutamic acid. For those who do not have a leaky gut, high glutamic acid will not be a problem. Hi Suzi, While bone broth does contain gelatin that will heal your gut, powdered bone broth is produced by long cooking, which is one of the reasons bone broth is high in glutamic acid.
So yes, it is possible. And yes, some people who have had neurological symptoms from headaches and migraines to stimming and seizures have had them triggered by high glutamic acid. If you would like to continue to heal your gut, try making meat stock, as that is what is recommended by Dr.
I have also written a book on the subject to try and clear this all up! It is available on this site. Thank you for the link! My book and article are based on the Gut and Psychology Syndrome by Dr. Natasha Campbell-McBride and some lab analysis of short cooked and long cooked broth, which showed the high concentration of glutamic acid in long cooked bone broth.
Sally Fallon Morrell wrote her article in , and is writing to the general audience regarding its attributes, before we had this additional information, and, 16 years ago. Sally reviewed my book on Meat Stock, saying the following:. Do you have a lot of practical questions? This book will answer them all, and then some. If you need encouragement, advice, and inspiration, this is the place to start. So, are there any powdered bone broths that you can recommend?
I found your article shared by Katie Kimball, Kitchen Stewardship.