1) Describe the key morphological features of H. naledi. What feature or combination of features was the most surprising to its discoverers?
Individually, the features of H. naledi were nothing extraordinary for an ancient primate.
However, when considered together, they raised some serious implications. This is because H. naledi has both Homo and Austrolopthicine traits. Specifically, their arboreal-adapted shoulders and fingers, outward-flaring hips, and relatively small brain are Australopithecine whereas their human-shaped skull, palms, wrists, thumbs, long biped-adapted long legs, and arched feet are Homo. Additionally, the dental structure of H. naledi showed an incongruous blend of Homo and Australopithecine tooth profiles. For example, they
…show more content…
naledi turns out to be 2 million years, scientists would likely classify H. naledi as a close relative of Australopithecines which also had climbing and bipedal adaptations. Its non-Australopithecine features and social behavior would likely be explained by having H. naledi as an ancestor of Homo and thus as the root of Homo features.
Should H. naledi be dated at 1 million years ago, it would imply that H. naledi was a species that evolved in parallel with the ancestors of modern humans. Their ritualistic behavior would be explained as being inherited from the same ancestor as modern humans. Their arboreal adaptations would be explained as the consequence of a divergent evolutionary path.
3) What age do you predict the species will be found to be? Why?
I predict that this species is a relatively modern one and will be around 1.5 million years old, the approximate age of Homo erectus and a time when bipedal adaptations were highly developed by means of longer legs and arched heels - two traits seen in H. naledi fossils.
My prediction is primarily based off of the H. naledi fossil's localization to the Rising Star Cave and the distribution of bones that indicate that they had been continuously deposited
In January 2005, contractors were excavating blocks of pavement to place electricity cables right at the corner of Ocean Street and Octavia Street, Narrabeen, NSW. The project was suspended due to an unanticipated discovery of a human skeleton buried underground, right beside a public bus shelter. The bones were in good state although some parts were missing. Fragments of primitive artefacts were also found around and inside the skeleton.
Paabo’s team discovered an mtDNA sequence from a finger bone they found from around 40,000 years ago, as carbon dating is one of the most commonly used methods of determining a fossil’s age. (Hammer, 70). Also, Neanderthal mtDNA is differs severely from modern human mtDNA. For example, Microcephalin is a gene for brain size during the development of the organism.
Ceratopsians and Pachycephalosaurs are closely related in their characteristics. Ceratopsians processed a saddle-shaped boney frill that extended from the skull to the neck and typically had horns over the nose and eyes. The most popular was the triceratops, which could reach over 26 feet and weigh in excess of twelve metric tons. Their frills served as two major functions. It protected the vulnerable neck from being harmed. The second major function that the frill provided was due to the fact that the frill contained a network of blood vessels on its underside, which were used as a means to get rid of excess heat. The Pachycephalosaurs were considered to be bipedal. They were also found to have thick skulls, flattened bodies, and tail that were covered in an array of body rods. Pachycephalosaurs were thought to have been more than fifteen feet long and processed a skull that was surrounded by a rounded dome of solid bone. It was thought that they used their heads in combat or mating contests, but that was disproved fairly recently, which I will discuss later in the paper. Both Ceratopsians and Pachycephalosaurs were “bird-hipped” and both of these suborders contained a backwards pubic bone. Both were Marginocephilia, or “fringed heads”, which is one of three clads under the Orinthiscia order. They were also herbivore dinosaurs that inherited their fringe at the back of the skull from earlier ancestors.(2) Their classi...
Hausler and Schmid suggest that speciation exists within the Hadar Australopithecines – that the specimens represent not just one species (afarensis), but two. To support their view, the scientists use calculations showing the sexual dimorphism (the presence of characteristics that differ between male and female members) among Australopithecines. Again, by studying sexual dimorphic traits, the scientists claim that “Lucy” is possibly male, not fema...
The partial remains of a skeleton belonging to a tiny female hominid that lived around 95K to 17Kya, was found in the Liang Bua cave on the island of Flores in Indonesia in 2003. This skeleton has unique traits. It has small body approximately 3’6” in length and an estimated body weight of 66 lbs. The 426 cc brain capacity led scientists to taxa the skeleton to a new species they called Homo floresiensis. Since the initial find, teeth and bones from as many as twelve H. floresiensis remains have been discovered at the Liang Bua cave which is the only known site where H. floresiensis has been found to date. This is the most recently discovered early human species so far. They had large teeth for their small size, they had no chins, their foreheads are receded, and they had relatively large feet in proportion to the short legs. Although they are small in body and brain size, H. floresiensis did make and use of stone tools. They hunted small elephants and large rodents. They had island predators such as giant Komodo dragons, and even may have used fire. However, arguments rising in the anthropology community and scientific world are questioning if the now nick named: “Hobbit”, of Flores Island, is the same species as modern day humans. Are they Homo species, or Homo sapiens with the medical condition called Cretinism? A severe hypothyroidism resulting in physical and mental stunting.
The Australopithecus Afarensis, which is an extinct hominid (A family of primates), is believed to have lived somewhere in between 2.9 – 3.9 million years ago. The A. Afarensis is believed to be one of the best known found species. They are believed to have been able to survive for at least 900,000 years ago if not more than that, being about four times as long of being around than our own species. The A. Afarensis is considered to be a gracile species, meaning to be smaller, more lightly built members of the genus Australopithecus. It is said that the A. Afarensis is the closest to being related to the genus homo, even including the Homo sapiens (The modern human species), when compared to any of the other known primates of that same time. The A. Afarensis fossils that have been discovered have mostly only been found in Eastern Africa
: The Plesiadapiforms are tiny mouse like creatures that lived during the 10 million period between the extinction of dinosaurs and appearance of humans. This could be our primate ancient ancestor. This primate has around more than 120 different species of its kind.
Feder and Park present a list of traits that are used by paleoanthropologists to distinguish the appearance of skeletal features and characterize these changes over time. Th...
The species A. afarensis is one of the better known australopithecines, with regards to the number of samples attributed to the species. From speculations about their close relatives, the gorilla and chimpanzee, A. afarensis’ probable social structure can be presumed. The species was named by Johanson and Taieb in 1973. This discovery of a skeleton lead to a heated debate over the validity of the species. The species eventually was accepted by most researchers as a new species of australopithecine and a likely candidate for a human ancestor.
Bipedalism had many advantages, but it also had many disadvantages and provided dangers to early hominids. Some of these disadvantages included i...
In 2000, Dr. Philip D. Gingerich, a paleontologist from the University of Michigan, and his associates discovered two primitive whale fossils in the Balochistan Province of Pakistan. By dating the limestone located in the Habib Rahi Formation of the Balochistan Province, Gingerich estimated these fossils to be about 47 million years old. According to author David Braun of National Geographic News, “The researchers have classified one, Rodhocetus balochistanensis, as a new species of an existing genus, and the other, Artiocetus clavis, as a new species and new genus” (Braun, 5). The discovery of these two fossils suggests that the closest living relative of these primitive whales could possibly be the modern day hippopotamus. This suggested relationship is based on similarities in the bone structure between the two animals.
Bindon, Jim 2004 Fossil Hominids. ANT 270 Notes. http://www.as.ua.edu/ant/bindon/ant270/lectures/ hominids1.pdf Delson, Eric 1981
extinct for 4000 years, it is difficult to tell exactly what they lived on, but
With its abundance of genera, the Burgess Shale is one of the world’s most important fossil fields. It’s discovery in 1909 led to over 100 years of paleontological study in the Canadian Rockies, a majority of which has been carried out in two quarries known as the Walcott and Raymond quarries (Hagadorn, 2002). Though he was originally in search of trilobites in the Burgess Shale Formation, paleontologist Charles Walcott also discovered a diverse group of soft- and hard-bodied fossils, from algae and sponges to chordates and cirripeds (Hagadorn, 2002). Soft-bodied fossils are incredibly rare due to their delicate structure and susceptibility to decay, so it is hard-bodied fossils that more regularly occur in fossil findings. However over 75,000 soft-bodied specimens have been found in the Burgess Shale formation (Hagadorn, 2002). These specimens are preserved in layers of shale formed from deposits of fine mud. One of the most significant species discovered is the Pikaia gracilens. Believed to be an early chordate, the Pikaia gracilens existed very close to the beginning of the evolutionary path that ultimately lead to humans (McGraw-Hill Encyclopedia, 2006).
1.9 million years ago, Homo Habilis of East Africa had evolved into an entirely new species known as Homo erectus. Homo erectus directly translates to "Upright man" and for good reason. One of largest anatomical advancements of Homo erectus was their arm and leg bones which were very similar in shape and proportions to that of modern day humans. "Their legs would have made Homo erectus efficient long distance runners like modern humans."(Dennis). Along with their longer more developed legs, Homo erectus's leg were also hairless which allowed them to evaporate sweat and thus be more efficient at not overheating. This advantage allowed Homo erectus to chase down four legged mammals to the point of heat exhaustion and thus drastically increase the efficiency their hunting tactics. Another change in the legs of Homo erectus was their slightly more narrow pelvises. This forced the size of a child’s head to be smaller at birth and undergo most of its development during childhood. (Dennis)