The oldest human footprints left behind on a muddy lakeside 1.5 million years ago appear to have been made by prehistoric hunting parties. Researchers examining the site where a series of tracks left by a barefooted early human in Ileret, northwest Kenya, have now found a total of 99 prints. They now believe that they belong to groups who all passed over the soft mud at the same time - perhaps even stalking some of the other animals whose prints are also preserved in the mud. The distinct tracks found at Ileret in Kenya (like the one above) are the oldest human footprints in the world . It provides some of the strongest evidence yet that the human ancestors that left the prints - Homo erectus - were sophisticated hunters. While their ancestors before them may have eaten meat they scavenged or from small prey they were able to catch, hunting parties suggests Homo erectus went after larger prey. Early human ancestors may have evolved to throw spears allowing them to hunt around two million years ago, a new study has suggested. Research by Dr Neil Roach has shown that the that the skeletons of Homo erectus had shoulders and collar bones that would have allowed them to hurl sticks accurately and powerfully. This would have enabled Homo erectus to become a proficient hunter, able to throw weapons like spears and rocks at potential prey. Dr Neil Roach, a palaeoanthropologist at the American Museum of Natural History in New York who led the study, said the prints appeared to have been made by adult males. He said that the tracks represent groups hunting for antelope or wildebeest. Speaking to Nature, Dr Roach said: 'What we can say is that we have a number of individuals, probably males, that are moving across a lake shore in a way that is consistent with how carnivores move. The researchers, who presented their findings at the annual meeting of the Paleoanthropology Society in San Francisco, hope to test their conclusions by studying the movement patterns of modern day subsistence hunters in Africa. The tracks in Ileret were first revealed in 2009 after researchers at Bournemouth University and Rutgers’ Koobi Fora Field School in Kenya, announced they had discovered a collection of 22 human prints. This deep print appears to have been left by a male Homo erectus that may have been part of a hunting party . Analysis of the print tracks (above) showed they had been made by a early human that walked much like we do . The prints were preserved in sediment that had once been the shoreline of an ancient lake. Alongside the human prints were those of birds including storks, pelicans as well as crocodiles, antelope, hippos, bovids and other predators. Professor Matthew Bennett, who was part of the team that originally studied the footprints, is shown above crouching in front of the ancient human tracks . Analysis of the footprints by Professor Matthew Bennett at Bournemouth University revealed the human prints had been made by a species with a similar bipedal stance and gait to modern humans, with a pronounced arch and short toes. He concluded that the prints had probably been left by Homo erectus - an extinct species of early human that disappeared around 200,000 years ago. They were among the longest surviving of all the human species - surviving for around 1.5 million years. There is some evidence that they may have also been able to control fire and cooked food. Footprints this old are extremely rare as they tend to erode away in a few thousand years, but are also valuable as they can give clues about behaviour. Dr Roach and his colleagues decided to study the prints in more detail in order to get a snapshot of the life led by Homo erectus. Over a four year excavation period a total of 483 prints in the Ileret sediment have now been uncovered - 99 of which were human. Unlike the grass-eating antelope and other hooved tracks preserved in the stone - whose tracks led from grasslands to the shore - the human prints all walked in one direction along the shoreline. This matched the behaviour of other hunting animals whose prints were also preserved. Previous work by Dr Roach has also shown that Homo erectus had developed the physic needed to be a deadly hunter. Homo erectus, shown in the reconstruction above, may have hunted large prey in groups or hunting parties . Fossilised skeletons how their shoulders and collar bones would have allowed them to throw sticks or spears both accurately and powerfully. Dr Roach said: 'There’s starting to be a consensus that around 2 million years ago we see more carnivory that has to do with hunting.' Curtis Marean, a palaeoanthropologist at Arizona State University in Tempe, said it was hard to tell from the prints exactly what had made them. He told Nature: 'It could be a group hunt, but it could also be lake shore foraging.' Tucking into meat for dinner helped early humans spread more quickly across the world and had a profound effect on human evolution, scientists say. The high-quality diet allowed mothers to wean babies earlier and have more children, meaning that human communities grew faster, according to researchers from Lund University in Sweden. The research compared 67 species of mammals, including humans, apes, mice and killer whales, and found a clear correlation between eating meat and earlier weaning. They found young of all species stop suckling when their brains have developed to a particular stage, but that carnivores reached this point more quickly than herbivores or omnivores. Eating meat enabled the breast-feeding periods and thereby the time between births to be shortened, according tot he researchers. Among natural fertility societies, the average duration of breast-feeding is 2 years and 4 months. This is not much in relation to the maximum lifespan of our species, around 120 years. It is even less if compared to our closest relatives: female chimpanzees suckle their young for 4 to 5 years, whereas the maximum lifespan for chimpanzees is only 60 years.
Researchers at the American Museum of Natural History in New York have found 99 footprints that appear to have been left by male Homo erectus .
The footprints - the oldest human tracks in the world, found in in Ileret, Kenya - may have been left by group hunting antelope or wildebeest .
It suggests Homo erectus were probably sophisticated and deadly hunters .