What kind of carnivores do humans eat

Isotopic evidence of early hominin diets. PNAS doi Teaford, M. Diet and the evolution of the earliest human ancestors. Watts, D. Scavenging by chimpanzees at Ngogo and the relevance of chimpanzee scavenging to early hominin behavioral ecology. Journal of Human Evolution 54, Werdelin, L. Plio-Pleistocene Carnivora of eastern Africa: species richness and turnover patterns. Zoological Journal of the Linnean Society , Wilkins et al.

Evidence for early hafted hunting technology. The Hardy-Weinberg Principle. Evolution Introduction. Life History Evolution. Mutations Are the Raw Materials of Evolution. Speciation: The Origin of New Species.

Avian Egg Coloration and Visual Ecology. The Ecology of Avian Brood Parasitism. The Maintenance of Species Diversity. Neutral Theory of Species Diversity. Population Genomics. Semelparity and Iteroparity. Geographic Mosaics of Coevolution. Comparative Genomics. Cybertaxonomy and Ecology. Ecological Opportunity: Trigger of Adaptive Radiation. Evidence for Meat-Eating by Early Humans. Resource Partitioning and Why It Matters. The Evolution of Aging. Citation: Pobiner, B. Nature Education Knowledge 4 6 The first major evolutionary change in the human diet was the incorporation of meat and marrow from large animals, which occurred by at least 2.

Aa Aa Aa. Eating Meat and Marrow. The diet of the earliest hominins was probably somewhat similar to the diet of modern chimpanzees: omnivorous, including large quantities of fruit, leaves, flowers, bark, insects and meat e. By at least 2.

When and where did hominin carnivory first occur? Figure 1. Who was eating this meat and marrow? Currently, there is fossil evidence for at least three species of hominins occurring at around 2. There are no butchered bones or stone tools found at stratigraphic levels associated with A.

While butchered bones have been found near A. Homo habilis skull from Koobi Fora, Kenya. What's so unique about this dietary strategy? The carnivory of hominins is unique among primates in three ways: 1 use of flaked stone tools to access animal resources; 2 acquisition of resources from animals much larger than the hominins themselves Figure 3 ; and 3 procurement of animal resources by scavenging.

Chimpanzees, our closest living relatives, routinely hunt, capture by hand, and eat meat from colobus or other smaller monkeys e. Mitani and Watts , but meat is a small proportion of their diet and they rarely scavenge Watts , most likely because they cannot efficiently digest carrion Ragir et al.

How this novel source of food was first recognized by hominins remains unknown. Hominins would likely not have been able to directly exploit grass as grassland expanded habitats across Africa - though see Sponheimer et al.

Homo erectus nearly 1 million years ago at Olorgesailie, Kenya. A reconstruction of an elephant butchery by Homo erectus nearly 1 million years ago at Olorgesailie, Kenya. Why did hominins start eating more meat and marrow? Meat and marrow are calorie-dense resources with essential amino acids and micronutrients Milton , and aquatic fauna offer resources rich in nutrients needed for brain growth e. Increasing the consumption of animal foods could have allowed hominins to increase their body size without losing mobility, agility, or sociality Milton But what was the frequency and quantity of nutrients obtained by hominins from animal tissues versus other foods?

This indicates that by at least 1. How did early humans obtain and utilize this meat and marrow? The earliest evidence for hunting technology in the form ofhafted spear points, currently dates back to about , years ago Wilkins et al. Persistence hunting has been suggested as a mode of hunting that would have been possible without advanced technology, but it's not clear how we would recognize this behavior in the fossil or archaeological record. The earliest firm evidence for the controlled use of fire at hearths in the form of burned seeds, wood, and flint, likely related to cooking, dates back to about , years ago Goren-Inbar et al.

Evidence for earlier traces of fire in eastern and southern Africa associated with hominins at Koobi Fora, Chesowanja, and Swartkrans e. While modern human gut proportions and size are unique among great apes Milton , and studies have found signatures of selection in genes in modern humans that may have played a role in adaptations to dietary changes Babbitt et al. Many zooarchaeologists who study Early Stone Age faunal assemblages think it's likely that at least some animal carcasses that were butchered by hominins, especially the larger ones, were obtained by scavenging.

Experimental models of the frequency and location of cut, percussion, and tooth marks e. Some unresolved questions in this area of research are: 1.

How can we evaluate whether confrontational scavenging or passive scavenging took place at any one site? What if more than one mode of carcass procurement took place? How did the acquisition of carcasses vary with different ecological affordances at different sites?

How does the mode of carcass procurement relate to the timing of hominin access to animal resources early access or late access? References and Recommended Reading Aiello, L. Bones: Ancient Men and Modern Myths. Academic Press, New York Share Cancel. Revoke Cancel. Keywords Keywords for this Article. Save Cancel. Flag Inappropriate The Content is: Objectionable. Flag Content Cancel. Email your Friend.

Submit Cancel. This content is currently under construction. Explore This Subject. Topic rooms within Evolution Close. No topic rooms are there. Lead Editor: Nick Bisceglia Evolution. Or Browse Visually. Other Topic Rooms Ecology. Student Voices. A rare example of a hypercarnivore that does not have carnassial teeth is the crabeater seal.

Carnivorous baleen whales, which have no teeth at all, use a similar strategy to strain krill from sea water. Their mouths contain rows of strong, flexible baleen plates made of keratin, the same protein that's in human fingernails. Animals that depend on meat for at least 50 percent of their diet are called mesocarnivores.

Along with meat, these animals will also eat fruits, vegetables and fungi. Mesocarnivores are typically small to mid-size species and often live close to human populations. Raccoons, foxes and coyotes are examples of mesocarnivores.

Hypocarnivores are carnivores that eat the least amount of meat — less than 30 percent of their diet, according to National Geographic. These animals, which can also be considered omnivores, eat fish, berries, nuts and roots, as well as meat. The world's largest animal is also the world's largest carnivore. The blue whale Balaenoptera musculus grows up to feet 30 meters long and weighs up to tons metric tons. The largest carnivore on land is the polar bear, which can weigh to 1, lbs.

The smallest carnivorous mammal is the least weasel. It grows no more than 16 inches long Though carnivores come in many shapes and sizes, they share a few similarities. Most carnivores have relatively large brains and high levels of intelligence. They also have less complicated digestive systems than herbivores.

It allows for neural connectivity and protects our nerves. Only animal source foods provide DHA in sufficient quantities. In addition to fatty acids, the brain requires various vitamins and minerals to extract energy and perform other bodily functions. Beta Carotene is a Vitamin A precursor found in plant foods, but the bioavailability is pitiful compared to preformed Vitamin A.

B Vitamins help convert fuel to energy and create the red blood cells that transport oxygen to our brains. B vitamins can also affect moods. Most people are deficient in vitamin B, which has been linked to depression.

Again, beef liver is an abundant source of vitamin B. Vitamin B12 is almost exclusively found in animal products. Vitamin K2 helps to regulate calcium in our bones and brains. Choline helps maintain the structure of cell membranes, which is responsible for memory and mental clarity. Deficits in choline can lead to cognitive impairments and problems with concentration and memory.

Our bodies make a small amount of choline, but most must come from food. Iron helps our cells generate energy, fight harmful pathogens, and circulate oxygen throughout the body. Copper regulates energy production, brain function, and iron metabolism. Zinc aids in serotonin synthesis and dopamine transport.

Iodine is necessary for synthesizing thyroid hormones, which are critical for brain growth and development. Fish, salmon roe , and eggs are all good dietary sources of iodine. While plants can provide some essential nutrients, most are far more bioavailable in animal meat than in vegetables or supplements.

The body can only utilize a portion of the nutrients it takes in—a principle called bioavailability. How much of a given nutrient your body ultimately absorbs is influenced by many factors, the most important of which is the source. The chart below shows that the energy yield from animal products far exceeds what is provided by plants.

There is no nutrient in plant foods that cannot be found in animals. But there are a few crucial nutrients that are impossible or very difficult to get insufficient amounts from commonly consumed plant foods. These include:. Though we have evolved from grass, shrub, and fruit eaters, the human body in its current form is designed to eat and run on meat. The study took into account a broad range of evidence, like genetic coding for a fat-rich diet, isotopes in bones of pre-historic humans showing the consumption of high-fat diets, likely from large animals, and the late appearance of tools for processing plant foods.

Development of the human brain in relation to food sources and hunting practices. Source: Times of Israel. Carnivores are shown to have a higher number of smaller fat cells, while omnivores have a smaller number of larger fat cells.

Humans have many small fat cells like all carnivores. Humans have a high stomach acidity level a pH of 1. Herbivorous primates have a stomach pH of around 4 to 6.

Most omnivores are between 2 and 4. Maintaining this level of acidity requires a lot of energy, as does retaining the stomach walls to contain that acidity. Presumably, humans would only evolve to this point if the bacteria levels in our diet were high enough to warrant the adaptation. This significantly reduces our ability to extract energy from plants. This gut morphology is an adaptation that favors meat consumption over plants.

As humans evolved, we gave up our ability to ferment fiber into fat and developed smaller colons as a trade-off for increasing our brain size.

Humans are the most dangerous animal with an unrivaled hunting prowess. Unlike our primate ancestors who continue to have shoulders adapted for climbing and swinging from trees, humans are the only species that can throw objects with incredible speed and accuracy—an evolutionary change that Human Evolutionary Biologist Neil Thomas Roach believes was an adaptation to carnivory.

Success at hunting allowed our ancestors to become part-time carnivores, eating more calorie-rich meat and fat and dramatically improving the quality of their diet. These dietary changes subsequently led to humans growing larger bodies, larger brains, and the ability to have more children. Carrying a higher amount of fat consumes energy and impairs our ability to chase or flee, but it also provides an insurance policy for survival during periods of food scarcity.

We know early humans crafted tools to help process meat. Evolution chose to forgo the ability to properly chew certain plant-based foods to allow for more room in the skull for our growing brains. Our brains are energy hogs and require lots of energy to function. In fact, since our prehistoric beginnings, our brains quadrupled in size.

And now since the agricultural revolution and the development of processed foods, our brains have begun to shrink.