Archaeology and Biological Anthropology

Both modern humans inhabiting various parts of the globe are members of the genus Homo and the species Sapiens, hence the term Homo sapiens. Homo sapiens arose in Africa after the rapid climatic shifts that happened over 200, 000 years ago. They, like early humans, lived in unstable weather environments by searching and collecting for food (Wood, 2016). However, modern humans are genetically similar to earlier humans in terms of skeletal thickness and brain circumference. The discovery of Homo Naledi in a cave in South Africa by Lee Berger significantly overturned the landscape of archaeology as well as biological anthropology. It brought in an all-new species to the human family tree thus making it one of the most significant discoveries of the 21st century back in 2013. The essay examines the fossil evidence of Homo naledi and its morphological aspects in comparison to the modern humans. A group of scientific excavators led by Lee Berger discovered the fossils in one of the caves in South Africa in 2013.
Fossil species: Homo naledi
In 2013, together with his team of underground astronauts, Lee embarked on a project that involved going deep into a hard-to-reach underground cave that went up to 40 feet in South Africa. Consequently, Lee made a lifetime discovery upon discovering hundreds of prehistoric bones. Furthermore, the bones included almost full skeletons of at least 15 people whose fossils dated nearly 2 million years ago (Schroeder et al., 2017). A look at the features of the various bones revealed resemblance to those of renowned prehominids such as Lucy, Australopithecus while some had a more physical association with modern humans than ever seen before in ancient history. The unique features of the discovered fossils led to the new classification of species termed as Homo naledi.
The discovery raised pertinent questions about the behavior and mental capacity of Homo naledi. For instance, how did it only contain the remains of one class of individuals? Does it imply that they buried the dead? If the answer to the questions is positive, then it implies that Homo naledi had some level of self-knowledge to the extent that they recognized death. Recognition of death is one of the critical and distinctive features of modern humans and defines what exactly makes us human. The next question is that were there equally advanced species that occupied the earth with us or before us? Scientists have always believed that only Homo sapiens had self-knowledge and awareness of the dead that involves burial of the body (Schroeder et al., 2017). However, the discovery of the new species, Homo naledi has changed everything and has inflicted a new thinking and perspective in the field of archaeology. One of the excavating scientists, Marina described the excavation process as one of the challenging and dangerous conditions in searching human origin given the size of the cave.
Morphological Analysis
Analysis of the fossils took place in 2014 and involved over 50 scientists who had come together to study the treasure trove of fossils. Homo naledi had features that resembled most of the primitive members of the genus, Homo but surprisingly had human features to warrant its classification in the same genus. Homo naledi was about 1.5 meters tall and weighed about 45 kilograms (Schroeder et al., 2017). The fact that the fossils were discovered from a room deep underground in the absence of other fossils from significant animals indicates a ritual behavior that was previously only linked to humans. The implication is that Homo naledi must have carried the bodies of the dead to the unique room hence their clear awareness of death.
The Hand and Foot of Homo naledi
The hands were extremely curved than almost all species of early hominin that demonstrated the ability to climb objects such as trees. However, the features of hands of Homo naledi also strongly indicated that it could use hands in using tools. The hands revealed a long and robust thumb as well as a derived wrist morphology that is common to the hand features of Neandertals and modern humans (Wood, 2016). Scientists have suggested that they were the adaptive and high intensity of manual manipulation. Nonetheless, hands had longer and curved finger bones as compared to most australopiths showing that the species frequently used its hands for grasping objects during climbing and suspension, say trees.
A combination of the features of the hands and the foot of the species indicated that it was adapted for climbing trees and walking upright as the dominant forms of movement (Wood, 2016). Most scientists agree that the features of the foot resemble the modern human foot in so many ways hence implying well adaptation for standing and walking on two feet. Moreover, they recognize the unique differences in more curved toe bones (proximal phalanges). However, the feet were fundamentally indistinguishable from those of modern humans. Some of the scientists suggested that a combination of the features of its feet and long-legs implied that it was suited for long-distance walking (National Geographic, 2017). Homo naledi is unique from other sapiens in that an aggregation of its features automatically distinguishes it from any previously known species. For instance, the finger bones are more curved compared to most early fossil human species including Lucy's species Australopithecus afarensis indicating ability to climb trees. Such a mix of human-like features and features that are more primitive suggest that it specialized in handling complex tools besides climbing locomotion.
The Skull and Brain of Homo naledi
Its skull and teeth resembled those of earliest known relatives of humans while the characteristics of its shoulders were similar to those of apes. Qualitative and quantitative analyses have shown that involves over one hundred measurements and ratios points to the direction that the cranial sample of Homo naledi, represents a structurally homogenous population (Laird et al., 2017). The population exhibits a morphological variation that is attributable to the genus, Homo. Homo naledi has a small cranial capacity that falls within the range of australopiths and a few specimens of early Homo that includes Homo habilis, Homo rudolfensis, Homo erectus, as well as Middle Pleistocene Homo (Wood, 2016). The features of the skull in question include cranial form, mandibular anatomy and its facial morphology. Nonetheless, it is worth noting that the head of Homo naledi has distinct features from those of existing Homo based on both quantitative and qualitative assessments.
The size of the skull also gives insights into the size of the brain for Homo naledi that scientists described as tinny brain and compares to the size of an average orange and its position pointed to the aspect that it had a slender body (Laird et al., 2017). The stature and body mass of Homo naledi are low in comparison to reported values for Homo erectus.
Location of the Discovery Site
The new species, Homo naledi, was found in a remote cave located at about 50 kilometres northwest of Johannesburg, South Africa. It is believed that the 1550 fossils excavated from the cave are parts of at least 15 adults, children and infants of the same species. The original discovery came about in 2013 in one of the caves known as the "Rising Star" located in the Cradle of Humankind World Heritage Site (National Geographic, 2017). The fossils were found lying in a chamber approximately 90 meters from the entrance of the cave that was only accessible through a chute of 18 centimeters wide. The excavation of the fossils took a team of 60 excavators and scientists 21 days to remove the fossils from the chamber.



Age of Homo naledi
The University of the Witwatersrand (Wits) paleoanthropologist Lee Berger has provided the age range of the new species to be between 236 000 to 335 000 years old. The implication is that the little-brained lineage was lingering from a more more extended period even as the human species was evolving from large-brained ancestors (Wood, 2016). The proposed range of its ages also overlaps with the early Middle Stone Age fueling a possibility that the stone-tool record in South Africa was not just the handiwork of the anatomically modern humans. The age ranges were based on a radiometric approach using flowstones (National Geographic, 2017). Other methods used included radiation dosage through assessment of radioactivity background. However, it is clear from the available information that getting a maximum age proved difficult hence the need for an age range. Yet, subsequent studies have tried to scientifically, estimate the age of Homo naledi by analyzing how its skull and teeth compare to other hominins' (Schroeder et al., 2017). Consequently, one settled on about 2 million years as the age of the new species while one by Simon Fraser University researcher Mana Dembo gave it 912 000 years and an error margin of plus or minus 1 million years.
Conclusion
The discovery of Homo naledi in 2013 by a paleoanthropologist, Lee Berger in Cradle of Humankind World Heritage Site have raised a lot of questions on the origin of the modern humans. The new species revealed various features some of which resembled the ones seen before in other species while others were just unique to the fossils (Wood, 2016). The hands and foot of the new species had significant as semblance to most of the fossils belonging to the genus Homo. However, the rounded toes showed some elements of primitive features but had some features shared by modern humans.
Radiocarbon dating has suggested that the age of the fossils range between 236 000 to 335 000 years with recent studies placing the range between 912 0000 - 2 million years (National Geographic, 2017). Morphologically, Homo naledi has many similar features to the modern humans but with specific primitive features some of which are not comparable to earlier known fossils (Wood, 2016). For instance, Homo naledi has a tinny brain, a mall skull as well as long legs. Additionally, the features show strong evidence to the modern human behavior of death awareness.

References
Laird, M.F., Schroeder, L., Garvin, H.M., Scott, J.E., Dembo, M., Radovčić, D., Musiba, C.M., Ackermann, R.R., Schmid, P., Hawks, J. and Berger, L.R., 2017. The skull of Homo naledi. Journal of human evolution, 104, pp.100-123.
National Geographic., 2017. Did This Mysterious Ape-Human Once Live Alongside Our Ancestors? Web. Retrieved from https://news.nationalgeographic.com/2017/05/homo-naledi-human-evolution-science/
Schroeder, L., Scott, J.E., Garvin, H.M., Laird, M.F., Dembo, M., Radovčić, D., Berger, L.R., de Ruiter, D.J. and Ackermann, R.R., 2017. Skull diversity in the Homo lineage and the relative position of Homo naledi. Journal of human evolution, 104, pp.124-135.
Wood, T.C., 2016. An evaluation of Homo naledi and "early" Homo from a young-age creationist perspective. Journal of Creation Theology and Science Series B: Life Sciences, 6, pp.14-30.