The hoof ( pl. : hooves ) is the tip of a toe of an ungulate mammal , which is covered and strengthened with a thick and horny keratin covering. Artiodactyls are even-toed ungulates, species whose feet have an even number of digits; the ruminants with two digits are the most numerous, e.g. giraffe , deer , bison , cattle , goat , pigs , and sheep . The feet of perissodactyl mammals have an odd number of toes, e.g. the horse , the rhinoceros , and the tapir . Although hooves are limb structures primarily found in placental mammals, hadrosaurs such as Edmontosaurus possessed hoofed forelimbs. The marsupial Chaeropus also had hooves.
100-397: Footprints are the impressions or images left behind by a person walking or running. Hoofprints and pawprints are those left by animals with hooves or paws rather than feet , while " shoeprints " is the specific term for prints made by shoes . They may either be indentations in the ground or something placed onto the surface that was stuck to the bottom of the foot. A " trackway " is
200-445: A crime scene can give vital evidence to the perpetrator of the crime. Shoes have many different prints based on the sole design and the wear that it has received – this can help to identify suspects. Photographs or castings of footprints can be taken to preserve the finding. Analysis of footprints and shoeprints is a specialist part of forensic science . Some detective work is relatively immediate, with criminals being tracked by
300-593: A 16-hour waking period, whereas other apes are generally awake from only sunup to sundown—and these additional hours were probably used for socializing. Because of this, fire usage is probably also linked to the origin of language . Artificial lighting may have also made sleeping on the ground instead of the trees possible by keeping terrestrial predators at bay. Migration into the frigid climate of Ice Age Europe may have only been possible because of fire, but evidence of fire usage in Europe until about 400–300,000 years ago
400-421: A 500,000-year timespan, and the sudden appearance of the typical human body plan. Cooking makes protein more easily digestible, speeds up nutrient absorption, and destroys food-borne pathogens, which would have increased the environment's natural carrying capacity, allowing group size to expand, causing selective pressure for sociality, requiring greater brain function. However, the fossil record does not associate
500-711: A baby's foot is from the large toe or adjacent to the large toe. It is not uncommon for military records of flight personnel to include bare foot inked impressions. Friction ridge skin protected inside flight boots tends to survive the trauma of a plane crash (and accompanying fire) better than fingers. Even though the US Armed Forces DNA Identification Laboratory (AFDIL), as of 2010, stored refrigerated DNA samples from all active duty and reserve personnel, almost all casualty identifications are effected using fingerprints from military ID card records (live scan fingerprints are recorded at
600-479: A brain volume of 310 cc (19 cu in) could have been safely delivered, which is 34–36% the mean adult size, compared to 40% in chimps and 28% in modern humans. This more aligns with the conclusions drawn from the Mojokerto child. A faster development rate could indicate a lower expected lifespan. Based on an average mass of 63 kg (139 lb) for males and 52.3 kg (115 lb) for females,
700-406: A consequence of a dietary shift to low-calcium meat. Kennedy could not explain why the calcium metabolism of H. erectus never adjusted. In 1985, American paleoanthropologist Mary Doria Russell and colleagues argued the supraorbital torus is a response to withstanding major bending moment which localizes in that region when significant force is applied through the front teeth, such as while using
800-423: A controversial claim. H. erectus males and females may have been roughly the same size as each other (i.e. exhibited reduced sexual dimorphism ), which could indicate monogamy in line with general trends exhibited in primates. Size, nonetheless, ranged widely from 146–185 cm (4 ft 9 in – 6 ft 1 in) in height and 40–68 kg (88–150 lb) in weight. It is unclear if H. erectus
900-417: A distinct genus of extinct ape. Homo erectus featured a flat face compared to earlier hominins; pronounced brow ridge; and a low, flat skull. The presence of sagittal , frontal , and coronal keels, which are small crests that run along these suture lines, has been proposed to be evidence of significant thickening of the skull, specifically the cranial vault . CT scan analyses reveal this to not be
1000-569: A group of at least 20 individuals. One of these trackways, based on the size of the footprints, may have been an entirely male group, which could indicate they were some specialised task group, such as a hunting or foraging party, or a border patrol. If correct, this would also indicate sexual division of labour, which distinguishes human societies from those of other great apes and social mammalian carnivores. In modern hunter gatherer societies who target large prey items, typically male parties are dispatched to bring down these high-risk animals, and, due to
1100-1085: A half a million years. Alternatively, a group of H. habilis may have been reproductively isolated , and only this group developed into H. erectus ( cladogenesis ). Because the earliest remains of H. erectus are found in both Africa and East Asia (in China as early as 2.1 Mya, in South Africa 2.04 Mya ), it is debated where H. erectus evolved. A 2011 study suggested that it was H. habilis who reached West Asia from Africa, that early H. erectus developed there, and that early H. erectus would then have dispersed from West Asia to East Asia ( Peking Man ), Southeast Asia ( Java Man ), back to Africa ( Homo ergaster ), and to Europe ( Tautavel Man ), eventually evolving into modern humans in Africa. Others have suggested that H. erectus / H. ergaster developed in Africa, where it eventually evolved into modern humans. H. erectus had reached Sangiran , Java, by 1.5 Mya, and
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#17327800424231200-436: A highly varied diet). Such versatility may have permitted H. erectus to inhabit a range of different environments and migrate beyond Africa. In 1999, British anthropologist Richard Wrangham proposed the "cooking hypothesis" which states that H. erectus speciated from the ancestral H. habilis because of fire usage and cooking 2 million years ago to explain the rapid doubling of brain size between these two species in only
1300-408: A humanlike curvature of the spine ( lordosis ) and the same number of respective vertebrae. It is largely unclear when human ancestors lost most of their body hair. Genetic analysis suggests that high activity in the melanocortin 1 receptor , which would produce dark skin, dates back to 1.2 Mya. This could indicate the evolution of hairlessness around this time, as a lack of body hair would have left
1400-548: A little further up the leg – these are not normally used for walking, but in some species with larger dewclaws (such as deer and pigs) they may touch the ground when running or jumping, or if the ground is soft. In the mountain goat, the dewclaw serves to provide extra traction when descending rocky slopes as well as additional drag on loose or slippery surfaces made of ice, dirt, or snow. Other cloven-hooved animals (such as giraffes and pronghorns ) have no dewclaws. In some so-called "cloven-hooved" animals, such as camels ,
1500-410: A second and distinct wave of H. erectus had colonized Zhoukoudian , China, about 780 kya (thousand years ago) . Early teeth from Sangiran are bigger and more similar to those of basal (ancestral) Western H. erectus and H. habilis than to those of the derived Zhoukoudian H. erectus . However, later Sangiran teeth seem to reduce in size, which could indicate a secondary colonization event of Java by
1600-419: A set of footprints in soft earth left by a life-form; animal tracks are the footprints, hoofprints, or pawprints of an animal . Footprints can be followed when tracking during a hunt or can provide evidence of activities. Some footprints remain unexplained, with several famous stories from mythology and legend . Others have provided evidence of prehistoric life and behaviours. The print left behind at
1700-440: A shift in female behavior which made it difficult for males to maintain a harem, and vice versa. Increasing brain size is often directly associated with a meatier diet and resultant higher caloric intake. Human entomophagy and therefore an increase in protein consumption through insects has also been proposed as a possible cause. However, it is also possible that the energy-expensive guts decreased in size in H. erectus , because
1800-462: A similar activity level have a DEE of 2,450 calories, of which 33% derives from fat, and 49% of the fat from animals. The cortical bone (the outer layer of the bone) is extraordinarily thickened, particularly in East Asian populations. The skullcaps have oftentimes been confused with fossil turtle carapaces , and the medullary canal in the long bones (where the bone marrow is stored, in
1900-414: A similar reason for the unusual thickening of the modern Australian Aboriginal skull, a result of a ritual popular in central and southeast Australian tribes where adversaries would wack each other with waddies (sticks) until knockout . The only fossil evidence regarding H. erectus group composition comes from four sites outside of Ileret , Kenya, where 97 footprints made 1.5 Mya were likely left by
2000-570: A skullcap in 1891 and a femur in 1892 ( Java Man ) dating to the late Pliocene or early Pleistocene at the Trinil site along the Solo River , which he named Pithecanthropus erectus ("upright apeman") in 1893. He attempted unsuccessfully to convince the European scientific community that he had found an upright-walking ape-man. Given few fossils of ancient humans had even been discovered at
2100-403: Is 84% higher than that for Australopithecus females, possibly due to an increased body size and a decreased growth rate. A 2011 study, assuming high energy or dietary fat requirements based on the abundance of large game animals at H. erectus sites, calculated a DEE of 2,700–3,400 kcal of which 27–44% derived from fat, and 44–62% of the fat from animal sources. In comparison, modern humans with
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#17327800424232200-556: Is an extinct species of archaic human from the Pleistocene , with its earliest occurrence about 2 million years ago. Its specimens are among the first recognizable members of the genus Homo . Several human species, such as H. heidelbergensis and H. antecessor , appear to have evolved from H. erectus , and Neanderthals , Denisovans , and modern humans are in turn generally considered to have evolved from H. heidelbergensis . H. erectus
2300-717: Is credited as the first human ancestor to have used fire, though the timing of this invention is debated mainly because campfires very rarely and very poorly preserve over long periods of time, especially thousands or millions of years. The earliest claimed fire sites are in Kenya, FxJj20 at Koobi Fora and GnJi 1/6E in the Chemoigut Formation , as far back as 1.5 Mya, and in South Africa, Wonderwerk Cave , 1.7 Mya. The first firekeepers are thought to have simply transported to caves and maintained naturally occurring fires for extended periods of time or only sporadically when
2400-893: Is credited with inventing the Acheulean stone tool industry, succeeding the Oldowan industry, and were the first to make lithic flakes bigger than 10 cm (3.9 in), and hand axes (which includes bifacial tools with only 2 sides, such as picks, knives, and cleavers ). Though larger and heavier, these hand axes had sharper, chiseled edges. They were likely multi-purpose tools, used in variety of activities such as cutting meat, wood, or edible plants. In 1979, American paleontologist Thomas Wynn stated that Acheulean technology required operational intelligence (foresight and planning), being markedly more complex than Oldowan technology which included lithics of unstandardized shape, cross-sections, and symmetry. Based on this, he concluded that there
2500-592: Is debated if the H. e. pekinensis inhabitants of Zhoukoudian , Northern China, were capable of controlling fires as early as 770 kya to stay warm in what may have been a relatively cold climate. In 1962, a 366 cm × 427 cm × 30 cm (12 ft × 14 ft × 1 ft) circle made with volcanic rocks was discovered in Olduvai Gorge . At 61–76 cm (2–2.5 ft) intervals, rocks were piled up to 15–23 cm (6–9 in) high. British palaeoanthropologist Mary Leakey suggested
2600-486: Is generally hypothesised that they lived in a monogamous society, as reduced sexual dimorphism in primates is typically correlated with this mating system. However, it is unclear if H. erectus did in fact exhibit humanlike rates of sexual dimorphism. If they did, then it would mean only female height increased from the ancestor species, which could have been caused by a shift in female fertility or diet, and/or reduced pressure on males for large size. This in turn could imply
2700-433: Is genetic rather than environmental. It is unclear if the condition is caused by increased bone apposition (bone formation) or decreased bone resorption , but Garn noted the stenosis is quite similar to the congenital condition in modern humans induced by hyper-apposition. In 1985, biological anthropologist Gail Kennedy argued for resorption as a result of hyperparathyroidism caused by hypocalcemia ( calcium deficiency),
2800-777: Is greater than the range of variation seen in modern humans and chimps, though less than that of gorillas. In an article published in 2021 titled "Interpopulational variation in human brain size: Implications for hominin cognitive phylogeny," it was found that the brain size of Asian H. erectus over the last 600,000 years overlaps significantly with modern human populations. Significantly, some small brained modern populations showed greater affinity with H. erectus than they did with other large brained and large bodied modern populations. The paper points out methodological flaws in current understanding of brain size increase in human evolution, where species averages are compared with fossils, which overlooks interpopulational variation. It also overlooks
2900-534: Is no definite consensus as to whether they should be classified as subspecies of H. erectus or H. sapiens or as separate species. Meganthropus , based on fossils found in Java, dated to between 1.4 and 0.9 Mya, was tentatively grouped with H. erectus in contrast to earlier interpretations of it as a giant species of early human although older literature has placed the fossils outside of Homo altogether. However, Zanolli et al. (2019) judged Meganthropus to be
3000-712: Is not a significant disparity in intelligence between H. erectus and modern humans and that, for the last 300,000 years, increasing intelligence has not been a major influencer of cultural evolution. However, a 1 year old H. erectus specimen shows that this species lacked an extended childhood required for greater brain development, indicating lower cognitive capabilities. A few sites, likely due to occupation over several generations, features hand axes en masse, such as at Melka Kunture , Ethiopia; Olorgesailie , Kenya; Isimila , Tanzania; and Kalambo Falls , Zambia. The earliest record of Acheulean technology comes from West Turkana , Kenya 1.76 Mya. Oldowan lithics are also known from
3100-799: Is notably absent. If these early European H. erectus did not have fire, it is largely unclear how they stayed warm, avoided predators, and prepared animal fat and meat for consumption. There was also a lower likelihood of naturally occurring fires due to lightning being less common in areas further north. It is possible that they only knew how to maintain fires in certain settings in the landscapes and prepared food some distance away from home, meaning evidence of fire and evidence of hominin activity are spaced far apart. Alternatively, H. erectus may have only pushed farther north during warmer interglacial periods—thus not requiring fire, food storage, or clothing technology— and their dispersal patterns indicate they generally stayed in warmer lower-to-middle latitudes. It
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3200-530: Is only demonstrated in modern humans. Like modern humans and unlike other great apes , there does not seem to have been a great size disparity between H. erectus males and females (size-specific sexual dimorphism ), though there is not much fossil data regarding this. Brain size in two adults from Koobi Fora measured 848 and 804 cc (51.7 and 49.1 cu in), and another significantly smaller adult measured 691 cc (42.2 cu in), which could possibly indicate sexual dimorphism, though sex
3300-495: Is possible that firestarting was invented and lost and reinvented multiple times and independently by different communities rather than being invented in one place and spreading throughout the world. The earliest evidence of hearths comes from Gesher Benot Ya'aqov, Israel, over 700,000 years ago, where fire is recorded in multiple layers in an area close to water, both uncharacteristic of natural fires. Artificial lighting may have led to increased waking hours—modern humans have about
3400-447: Is possible that male–male bonding and male–female friendships were important societal aspects. Because H. erectus children had faster brain growth rates, H. erectus likely did not exhibit the same degree of maternal investment or child-rearing behaviours as modern humans. Because H. erectus males and females are thought to have been about the same size compared to other great apes (exhibit less size-specific sexual dimorphism), it
3500-466: Is possible that they were the first in the human line to do so, though the fragmentary fossil record for earlier species makes this unclear. If yes, then there was a substantial and sudden increase in female height. Certain features of sexual dimorphism are often identified in the possibility of determining sex such as lack of muscle marking. H. erectus had about the same limb configurations and proportions as modern humans, implying humanlike locomotion,
3600-430: Is sometimes considered as a wide-ranging, polymorphous species. Due to such a wide range of variation, it has been suggested that the ancient H. rudolfensis and H. habilis should be considered early varieties of H. erectus . The primitive H. e. georgicus from Dmanisi , Georgia has the smallest brain capacity of any known Pleistocene hominin (about 600 cc), and its inclusion in the species would greatly expand
3700-573: Is sometimes not even regarded as H. erectus . It is debated whether the African H. e. ergaster is a separate species (and that H. erectus evolved in Asia, then migrated to Africa), or is the African form ( sensu lato ) of H. erectus ( sensu stricto ) . In the latter, H. ergaster has also been suggested to represent the immediate ancestor of H. erectus . It has also been suggested that H. ergaster instead of H. erectus , or some hybrid between
3800-409: Is typically exacerbated in dark-skinned people living in higher latitudes due to vitamin D deficiency. Hairlessness is generally thought to have facilitated sweating, but reduction of parasite load and sexual selection have also been proposed. The 1.8 Ma Mojokerto child specimen from Java, who died at about 1 year of age, presented 72–84% of the average adult brain size, which is more similar to
3900-751: The Dutch East Indies . Because no directed expedition had ever discovered human fossils (the few known had all been discovered by accident), and the economy was strained by the Long Depression , the Dutch government refused to fund Dubois. In 1887, he enlisted in the Dutch East India Army as a medical officer, and was able to secure a post in 1887 in the Indies to search for his " missing link " in his spare time. On Java , he found
4000-482: The Second Sino-Japanese War after an attempt to smuggle them out of China for safekeeping. Only casts remain. Similarities between Java Man and Peking Man led Ernst Mayr to rename both as Homo erectus in 1950. Throughout much of the 20th century, anthropologists debated the role of H. erectus in human evolution . Early in the century, due in part to the discoveries at Java and Zhoukoudian,
4100-402: The navicular bone . The hoof consists of the hoof wall , the bars of the hoof, the sole and frog and soft tissue shock absorption structures. The weight of the animal is normally borne by both the sole and the edge of the hoof wall. Hooves perform many functions, including supporting the weight of the animal, dissipating the energy impact as the hooves strike the ground or surface, protecting
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4200-560: The "hoof" is not properly a hoof – it is not a hard or rubbery sole with a hard wall formed by a thick nail – instead it is a soft toe with little more than a nail merely having an appearance of a hoof. Some odd-toed ungulates ( equids ) have one hoof on each foot; others have (or had) three distinct hooved or heavily nailed toes, or one hoof and two dewclaws. The tapir is a special case, having three toes on each hind foot and four toes on each front foot. Hooves grow continuously. In nature, wild animals are capable of wearing down
4300-666: The 1970s, propelled most notably by Richard Leakey , more were being unearthed in East Africa predominantly at the Koobi Fora site, Kenya, and Olduvai Gorge , Tanzania. Archaic human fossils unearthed across Europe used to be assigned to H. erectus , but have since been separated as H. heidelbergensis as a result of British physical anthropologist Chris Stringer 's work. It has been proposed that H. erectus evolved from H. habilis about 2 Mya, though this has been called into question because they coexisted for at least
4400-474: The Christian poem Footprints being one of the best known. Prints or impressions of a child's feet can be kept as a memento by parents. Usually this is done using paint. The impressions of celebrity 's feet, usually in concrete , may be kept in a collection such as that outside Grauman's Chinese Theatre . Hoof The hoof surrounds the distal end of the second phalanx , the distal phalanx , and
4500-633: The Zhoukoudian or some closely related population. " Wushan Man " was proposed as Homo erectus wushanensis , but is now thought to be based upon fossilized fragments of an extinct non-hominin ape. Since the discovery of Java Man in 1893, there has been a trend in paleoanthropology of reducing the number of proposed species of Homo , to the point where H. erectus includes all early ( Lower Paleolithic ) forms of Homo sufficiently derived from H. habilis and distinct from early H. heidelbergensis (in Africa also known as H. rhodesiensis ). It
4600-454: The basic cranial features are maintained. In a wider sense, H. erectus had mostly been replaced by H. heidelbergensis by about 300 kya, with possible late survival of H. erectus soloensis in Java an estimated 117-108 kya. Homo erectus is the most long-lived species of Homo , having survived for almost two million years. By contrast, Homo sapiens emerged about a third of a million years ago. Regarding many archaic humans , there
4700-562: The belief that modern humans first evolved in Asia was widely accepted. A few naturalists— Charles Darwin the most prominent among them—theorized that humans' earliest ancestors were African. Darwin had pointed out that chimpanzees and gorillas , humans ' closest relatives, evolved and exist only in Africa. Darwin did not include orangutans among the great apes of the Old World, likely because he thought of orangutans as primitive humans rather than apes. While Darwin considered Africa as
4800-481: The case. However, the squamous part of occipital bone , particularly the internal occipital crest , at the rear of the skull is notably thicker than that of modern humans, likely a basal (ancestral) trait. The fossil record indicates that H. erectus was the first human species to have featured a projecting nose, which is generally thought to have evolved in response to breathing dry air in order to retain moisture. American psychologist Lucia Jacobs hypothesized that
4900-403: The daily energy expenditure (DEE)—the amount of calories metabolized in one day—was estimated to be about 2271.8 and 1909.5 kcal , respectively. This is similar to that of earlier Homo , despite a marked increase in activity and migratory capacity, likely because the longer legs of H. erectus were more energy-efficient in long-distance movement. Nonetheless, the estimate for H. erectus females
5000-442: The diet of these hominins. At the 1.5 Mya Trinil H. K. site, Java, H. erectus likely gathered fish and shellfish. Dentally, H. erectus mouths were not as versatile as those of ancestor species, capable of processing a narrower range of foods. However, tools were likely used to process hard foods, thus affecting the chewing apparatus. This combination may have instead increased dietary flexibility (though this does not equate to
5100-445: The emergence of H. erectus with fire usage nor with any technological breakthrough for that matter, and cooking likely did not become a common practice until after 400 kya. Java Man's dispersal through Southeast Asia coincides with the extirpation of the giant turtle Megalochelys , possibly due to overhunting as the turtle would have been an easy, slow-moving target which could have been stored for quite some time. H. erectus
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#17327800424235200-408: The equine world, the expression, "no foot, no horse" emphasizes the importance of hoof health. Hoof care is important in the equine industry . Problems that can arise with poor horse hoof care include hoof cracks, thrush, abscesses and laminitis . A cow hoof is cloven, or divided, into two approximately equal parts, usually called claws. Approximately 95% of lameness in dairy cattle occurs in
5300-410: The exterior wall of the hoof. From the outside, a hoof is made up of the stratum externum, the stratum medium, the stratum internum and the dermis parietis. The stratum externum and the stratum medium are difficult to distinguish, the stratum externum is thin and the stratum medium is what makes up the bulk of the hoof wall. Inside the hoof wall is a laminar junction , a soft tissue structure that allows
5400-479: The eyes, and transitions into a bar covering the ears, connecting all the way in the back of the skull, meaning blows to any of these regions can be effectively dissipated across the skull; and the sagittal keel protects the top of the braincase. Many skullcaps bear usually debilitating fractures, such as the Peking Man skull X, yet they can show signs of surviving and healing. Anthropologist Peter Brown suggested
5500-415: The fact that some modern populations have not seen any dramatic brain size increase relative to H. erectus with most of the increase occurring in northern populations, which has the result of obscuring interpopulational variation. As the authors write '...the increase in the mean of H. sapiens cranial capacity is to a large extent due to an increase in the upper limit with a much less pronounced increase in
5600-412: The faster brain growth trajectory of great apes than modern humans. This indicates that H. erectus was probably not cognitively comparable to modern humans, and that secondary altriciality —an extended childhood and long period of dependency due to the great amount of time required for brain maturation—evolved much later in human evolution, perhaps in the modern human/Neanderthal last common ancestor. It
5700-521: The feet. Lameness in dairy cows can reduce milk production and fertility, and cause reproductive problems and suffering. For dairy farm profitability, lameness, behind only infertility and mastitis , is the third most important cow health issue. Hoof trimmers trim and care for bovine hooves, usually dairy cows . Hooves can be trimmed with a sharp knife while the cow is restrained and positioned with ropes. Professional hoof-trimming tend to use angle grinders and some type of hoof trimming crush to make
5800-452: The first in the Homo lineage. H. erectus tracks near Ileret , Kenya, also indicate a human gait . A humanlike shoulder suggests an ability for high speed throwing. It was once thought that Turkana boy had 6 lumbar vertebra instead of the 5 seen in modern humans and 11 instead of 12 thoracic vertebrae , but this has since been revised, and the specimen is now considered to have exhibited
5900-500: The footprints may be given scientific names ( ichnospecies ). Grallator is one example of an ichnogenus based on ichnites. Strictly speaking, an ichnospecies is the name of the trace fossil, not of the animal that made it. An international team's discovery of a set of 1.5 million-year-old human ancestor footprints in Ileret, Kenya provides the earliest direct evidence of a modern human style of upright walking. The team believe that
6000-496: The footprints they left in the snow leading from the crime scene to their home or hiding place. This is usually reported as a humorous story in news publications. Footprints can also allow the detective to find the approximate height from, footprint and shoeprint. The Foot tends to be approximately 15% of the person's average height. Individualistic characteristics of the footprints like numerous creases, flatfoot character, horizontal and vertical ridges, corns, deformities etc. can help
6100-525: The forensic scientist in cases pertaining to criminal identification. In some forensic cases, the need may also arise to estimate body weight from the size of the footprints. Footprints have been shown to have determined the height and the sex of the individual. Friction ridge skin present on the soles of the feet and toes (plantar surfaces) is as unique in its ridge detail as are the fingers and palms (palmar surfaces). When recovered at crime scenes or on items of evidence, sole and toe impressions can be used in
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#17327800424236200-499: The hoof as it continuously grows, but captive domesticated species often must undergo specific hoof care for a healthy, functional hoof. Proper care improves biomechanical efficiency and prevents lameness. If not worn down enough by use, such as in the dairy industry, hooves may need to be trimmed. However, too much wear can result in damage of the hooves, and for this reason, horseshoes and oxshoes are used by animals that routinely walk on hard surfaces and carry heavy weight. Within
6300-444: The hoof to withstand the demands of force transmission it undergoes. This tissue structure binds the inner surface of the hoof wall, the dermis parietis and the outer surface of the third phalanx. Most even-toed ungulates (such as sheep , goats , deer , cattle , bison and pigs ) have two main hooves on each foot, together called a cloven hoof . Most of these cloven-hooved animals also have two smaller hooves called dewclaws
6400-509: The increasing dependence on meat. With an emphasis on teamwork, division of labor, and food sharing, hunting and gathering was a dramatically different subsistence strategy from previous modes. H. erectus sites frequently are associated with assemblages of medium- to large-sized game, namely elephants , rhinos , hippos , bovines , and boars . H. erectus would have had considerable leftovers, potentially pointing to food sharing or long-term food preservation (such as by drying) if most of
6500-752: The kill was indeed utilized. It is possible that H. erectus grew to become quite dependent on large-animal meat, and the disappearance of H. erectus from the Levant is correlated with the local extinction of the straight-tusked elephant . Nonetheless, H. erectus diet likely varied widely depending upon location. For example, at the 780 kya Gesher Benot Ya'aqov site, Israel, the inhabitants gathered and ate 55 different types of fruits, vegetables, seeds, nuts, and tubers, and it appears that they used fire to roast certain plant materials that otherwise would have been inedible; they also consumed amphibians, reptiles, birds, aquatic and terrestrial invertebrates, in addition to
6600-400: The large ape gut is used to synthesize fat by fermenting plant matter, which was replaced by dietary animal fat, allowing more energy to be diverted to brain growth. This would have increased brain size indirectly while maintaining the same caloric requirements of ancestor species. H. erectus may have also been the first to use a hunting and gathering food collecting strategy as a response to
6700-596: The largest scale." (1889, pp. 155–156). In 1949, the species was reported in Swartkrans Cave, South Africa, by South African paleoanthropologists Robert Broom and John Talbot Robinson , who described it as " Telanthropus capensis ". Homo fossils have also been reported from nearby caves, but their species designation has been a tumultuous discussion. A few North African sites have additionally yielded H. erectus remains, which at first were classified as " Atlantanthropus mauritanicus " in 1951. Beginning in
6800-552: The limbs) is extremely narrowed (medullary stenosis ). This degree of thickening is usually exhibited in semi-aquatic animals which used their heavy ( pachyosteosclerotic ) bones as ballasts to help them sink, induced by hypothyroidism . Male specimens have thicker cortical bone than females. It is largely unclear what function this could have served. All pathological inducers would leave scarring or some other indicator not normally exhibited in H. erectus . Before more complete skeletons were discovered, Weidenreich suggested H. erectus
6900-415: The low success rate, female parties focus on more predictable foods. Based on modern day savanna chimp and baboon group composition and behavior, H. erectus ergaster may have lived in large, multi-male groups in order to defend against large savanna predators in the open and exposed environment. However, dispersal patterns indicate that H. erectus generally avoided areas with high carnivore density. It
7000-424: The lower limit relative to our H. erectus sample. And this increase in the upper limit seems to be more pronounced in northern populations – which may be a result of correlated increases in body size in addition to climatic factors. Consequently, the authors argue that purely based on brain size similarities, Asian H. erectus could be re-classified as a subspecies of H. sapiens , that is H. sapiens soloensis - as
7100-661: The most probable birthplace of human ancestors, he also made the following statement about the geographic location of human origins in his book The Descent of Man, and Selection in Relation to Sex : "... it is useless to speculate on this subject; for two or three anthropomorphous apes, one the Dryopithecus …, existed in Europe during the Miocene age; and since so remote a period the earth has certainly undergone many great revolutions, and there has been ample time for migration on
7200-521: The most productive H. erectus site in the world. Continued interest in Java led to further H. erectus fossil discoveries at Ngandong ( Solo Man ) in 1931, Mojokerto (Java Man) in 1936, and Sangiran (Java Man) in 1937. The Sangiran site yielded the best preserved Java Man skull. German paleoanthropologist Franz Weidenreich provided much of the detailed description of the Chinese specimens in several monographs. The original specimens were lost during
7300-402: The mouth as a third hand to carry objects. In 2004, Noel Boaz and Russel Ciochon suggested it was a result of a cultural practice, wherein H. erectus would fight each other with fists, stones, or clubs to settle disputes or battle for mates, since the skull is reinforced in key areas. The mandible is quite robust, capable of absorbing heavy blows (no "glass jaw"); the heavy brow ridge protects
7400-409: The nighttime temperature can drop to 10 or 5 °C (50 or 41 °F)—so they may have required hair to stay warm, unlike early Homo which inhabited lower, hotter elevations. Populations in higher latitudes potentially developed lighter skin to prevent vitamin D deficiency . A 500–300 kya H. erectus specimen from Turkey was diagnosed with the earliest known case of tuberculous meningitis , which
7500-403: The opportunity arose. Maintaining fires would require firekeepers to have knowledge of slow-burning materials such as dung. Fire becomes markedly more abundant in the wider archaeological record after 400,000–300,000 years ago, which can be explained as some advancement in fire management techniques took place at this time or human ancestors only opportunistically used fire until this time. It
7600-443: The practical application of this is unclear. Nonetheless, the mandibular bodies of H. erectus are somewhat thinner than those of early Homo . The premolars and molars also have a higher frequency of pits than H. habilis , suggesting H. erectus ate more brittle foods (which cause pitting). These all indicate that the H. erectus mouth was less capable of processing hard foods and more at shearing through tougher foods, thus reducing
7700-540: The prints were probably formed by the species Homo erectus . Footprints suggesting the first making of shoes or sandals due to having crisp edges, no signs of toes found and three small divots where leather tying laces/straps would have been attached have been in South Africa dating back to between 73,000 and 136,000 PB. Further, in September 2021, scientists reported the discovery of human footprints in
7800-586: The process quicker and less physically demanding on the hoof trimmer. A hoof trimmer using modern machinery may trim the hooves of more than 10,000 cows per year. The trimmer shapes the hooves to provide the optimal weight-bearing surface. A freshly trimmed hoof may be treated with copper sulfate pentahydrate to prevent foot rot . Hooves have historical significance in ceremonies and games. They have been used in burial ceremonies. Homo erectus Homo erectus ( / ˌ h oʊ m oʊ ə ˈ r ɛ k t ə s / lit. ' upright man ' )
7900-579: The projecting nose instead allowed for distinguishing the direction different smells come from (stereo olfaction) to facilitate navigation and long-distance migration. The average brain size of Asian H. erectus is about 1,000 cc (61 cu in). However, markedly smaller specimens have been found in Dmanisi, Georgia ( H. e. georgicus ); Koobi Fora and Olorgesailie , Kenya; and possibly Gona , Ethiopia. Overall, H. erectus brain size varies from 546–1,251 cc (33.3–76.3 cu in), which
8000-400: The range of variation of H. erectus to perhaps include species as H. rudolfensis , H. gautengensis , H. ergaster , and perhaps H. habilis . However, a 2015 study suggested that H. georgicus represents an earlier, more primitive species of Homo derived from an older dispersal of hominins from Africa, with H. ergaster/erectus possibly deriving from a later dispersal. H. georgicus
8100-410: The rock piles were used to support poles stuck into the ground, possibly to support a windbreak or a rough hut. Some modern-day nomadic tribes build similar low-lying rock walls to build temporary shelters upon, bending upright branches as poles and using grasses or animal hide as a screen. Dating to 1.75 Mya, it is the oldest claimed evidence of architecture. The earliest evidence of cave habitation
8200-482: The same manner as finger and palm prints to effect identifications. Footprint (toe and sole friction ridge skin) evidence has been admitted in courts in the United States since 1934. The footprints of infants, along with the thumb or index finger prints of mothers, are still commonly recorded in hospitals to assist in verifying the identity of infants. Often, the only identifiable ridge detail that can be seen on
8300-580: The site, and the two seemed to coexist for some time. The earliest records of Acheulean technology outside of Africa date to no older than 1 Mya, indicating it only became widespread after some secondary H. erectus dispersal from Africa. On Java, H. erectus produced tools from shells at Sangiran and Trinil. Spherical stones, measuring 6–12 cm (2.4–4.7 in) in diameter, are frequently found in African and Chinese Lower Paleolithic sites, and were potentially used as bolas ; if correct, this would indicate string and cordage technology. H. erectus
8400-584: The skin exposed to harmful UV radiation . It is possible that exposed skin only became maladaptive in the Pleistocene, because the increasing tilt of the Earth (which also caused the ice ages ) would have increased solar radiation bombardment- which would suggest that hairlessness first emerged in the australopithecines. However, australopithecines seem to have lived at much higher, much colder elevations—typically 1,000–1,600 m (3,300–5,200 ft) where
8500-674: The state of New Mexico that are understood to be 23,000 years old, around the time of the last Ice Age . Later studies, reported in October 2023, confirmed that the age of the human footprints to be "up to 23,000 years old". The appearance of footprints, or marks interpreted as footprints, have led to numerous myths and legends. Some locations use such imprints as tourist attractions. Détailed article Petrosomatoglyph Examples of footprints in myth and legend include: The imagery of footprints has been used in many areas of popular culture. Several poems and songs have been written about them, with
8600-418: The time such cards are issued). When friction ridge skin is not available from military personnel's remains, DNA and dental records are used to confirm identity. Footprints have been preserved as fossils and provide evidence of prehistoric life. Known as " ichnites ", these trace fossils can give clues to the behaviour of specific species of dinosaur . The study of such fossils is known as ichnology and
8700-484: The time, they largely dismissed his findings as a malformed non-human ape. The significance of these fossils would not be realized until the 1927 discovery of what Canadian paleoanthropologist Davidson Black called " Sinanthropus pekinensis " (Peking Man) at the Zhoukoudian cave near Beijing , China. Black lobbied across North America and Europe for funding to continue excavating the site, which has since become
8800-439: The tissues and bone within the hoof capsule, and providing traction for the animal. Numerous factors can affect hoof structure and health, including genetics, hoof conformation, environmental influences, and athletic performance of the animal. The ideal hoof has a parallel hoof-pastern axis, a thick hoof wall, adequate sole depth, a solid heel base and growth rings of equal size under the coronary band. There are four layers within
8900-515: The two, was the immediate ancestor of other archaic humans and modern humans. It has been proposed that Asian H. erectus have several unique characteristics from non-Asian populations ( autapomorphies ), but there is no clear consensus on what these characteristics are or if they are indeed limited to only Asia. Based on supposed derived characteristics, the 120 kya Javan H. e. soloensis has been proposed to have speciated from H. erectus , as H. soloensis , but this has been challenged because most of
9000-592: The usual large creatures such as elephant and fallow deer . At the 1.95 Mya FwJJ20 lakeside site in the East Turkana Basin, Kenya, the inhabitants ate (alongside the usual bovids, hippos, and rhinos) aquatic creatures such as turtles , crocodiles , and catfish . The large animals were likely scavenged at this site, but the turtles and fish were possibly collected live. In East Africa between 2.0 and 1.4 Mya, carcasses of C 4 -grazing ungulates, particularly alcelaphins , featured increasingly prominently in
9100-447: The variety of foods it could process, likely as a response to tool use. Like modern humans, H. erectus varied widely in size, ranging from 146–185 cm (4 ft 9 in – 6 ft 1 in) in height and 40–68 kg (88–150 lb) in weight, thought to be due to regional differences in climate, mortality rates, or nutrition. Among primates, this marked of a response to environmental stressors ( phenotypic plasticity )
9200-496: Was German naturalist Ernst Haeckel , who argued that the first human species evolved on the now-disproven hypothetical continent " Lemuria " in what is now Southeast Asia, from a species he termed " Pithecanthropus alalus " ("speechless apeman"). "Lemuria" had supposedly sunk below the Indian Ocean , so no fossils could be found to prove this. Nevertheless, Haeckel's model inspired Dutch scientist Eugène Dubois to journey to
9300-401: Was a gigantic species, thickened bone required to support the massive weight. It was hypothesized that intense physical activity could have induced bone thickening, but in 1970, human biologist Stanley Marion Garn demonstrated there is a low correlation between the two at least in modern humans. Garn instead noted different races have different average cortical bone thicknesses, and concluded it
9400-601: Was an apex predator ; sites generally show consumption of medium to large animals, such as bovines or elephants , and suggest the development of predatory behavior and coordinated hunting. H. erectus is associated with the Acheulean stone tool industry , and is postulated to have been the earliest human ancestor capable of using fire, hunting and gathering in coordinated groups, caring for injured or sick group members, and possibly seafaring and art (though examples of art are controversial, and are otherwise rudimentary and few and far between). Intentional seafaring has also been
9500-495: Was anatomically capable of speech, though it is postulated they communicated using some proto-language . Contrary to the view Charles Darwin expressed in his 1871 book Descent of Man , many late-19th century evolutionary naturalists postulated that Asia, not Africa, was the birthplace of humankind as it is midway between Europe and America, providing optimal dispersal routes throughout the world (the Out of Asia theory ). Among these
9600-417: Was previously believed that, based on the narrow pelvis of Turkana boy, H. erectus could only safely deliver a baby with a brain volume of about 230 cc (14 cu in), equating to a similar brain growth rate as modern humans to achieve the average adult brain size of 600–1,067 cc (36.6–65.1 cu in). However, a 1.8 Ma female pelvis from Gona, Ethiopia, shows that H. erectus babies with
9700-496: Was suggested by earlier authors. Dentally, H. erectus have the thinnest enamel of any Plio–Pleistocene hominin. Enamel prevents the tooth from breaking from hard foods but impedes shearing through tough foods. The bodies of the mandibles of H. erectus , and all early Homo , are thicker than those of modern humans and all living apes. The mandibular body resists torsion from the bite force or chewing, meaning their jaws could produce unusually powerful stresses while eating, but
9800-509: Was the first human ancestor to spread throughout Eurasia , with a continental range extending from the Iberian Peninsula to Java . Asian populations of H. erectus may be ancestral to H. floresiensis and possibly to H. luzonensis . The last known population of H. erectus is H. e. soloensis from Java, around 117,000–108,000 years ago. H. erectus had a more modern gait and body proportions, and
9900-410: Was the first human species to have exhibited a flat face, prominent nose, and possibly sparse body hair coverage. Though the species' brain size certainly exceeds that of ancestor species, capacity varied widely depending on the population. In earlier populations, brain development seemed to cease early in childhood, suggesting that offspring matured faster, thus limiting cognitive development. H. erectus
10000-500: Was undetermined. Another case that depicts the difficulty of assigning sex to the fossil record is a few samples taken in Olduvai Gorge. In 1960, in Olduvai Gorge two skulls identified as OH12 and OH9, were found to be that of H. erectus with a cranial capacities of 1000 cc and 700 cc. It is unclear if sexual dimorphism is at play here since the remains are fragmentary. If H. erectus did not exhibit sexual dimorphism, then it
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