A Closer Look at Lucy: Sexual Dimorphism and Speciation in Australopithecus
In his peer-reviewed article, “Sexing fossils: a boy named Lucy?,” James Shreeve discusses, in detail, a study on sexual dimorphism and possible speciation in Australopithecines in Hadar, Ethiopia, based on the famous A. afarensis specimen, “Lucy.” In the article, “Lucy’s kind takes humanlike turn,” the author addresses sexual dimorphism and speculates on sex-based differences in behaviors in A. afarensis. The two articles have differences and commonalities with each other in content and both present research methods and conclusions on topics including sexual dimorphism, sex-based behaviors, and speciation in Australopithecines, which receive critical analysis.
A study performed by Martin Hausler and Peter Schmid of the University of Zurich, Switzerland, appeared in the October 1995 issue of Journal of Human Evolution, igniting controversy over the 1974 Australopithecus discoveries in Hadar, Ethiopia. The most famous of the Hadar specimens is the 3-million-year-old skeleton, “Lucy,” who was recovered by paleoanthropologist, Donald Johanson. In his article, Shreeve presents the methods and findings of Hausler and Schmid’s study as well as some counter arguments from other scientists in the field.
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...
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...“Sexing fossils: a boy named Lucy?,” a peer-reviewed article by James Shreeve, and the article “Lucy’s kind takes humanlike turn” address subjects including sexual dimorphism, sex-based behaviors, and speciation of Australopithecines. While the two articles differ in the research and findings presented, they share a main, significant conclusion about Australopithecines, which is the sexual dimorphism in body size. Male A. afarensis are evidently larger than females, although there is some disagreement as to how much larger (the degree of sexual dimorphism).
Works Cited
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p1297(2). Retrieved April 5, 2004 from Infotrac Onefile database.
Over the last few hundred years, more and more has been added to the world’s fossil collection, fossils from all over the world. New theories have been created and old theories have almost been proven about the evolution of man. For example, we have proof that different species of man existed with certain types of DNA sequences and instincts, some we may not have anymore, or some that other species did not have back then. Even though it is subjected to much debate, one of the most widely accepted theories however, is that Homo sapiens interbred with the slightly more primitive species of man, the Neanderthal.
The evolution of man is constantly in question. While we are reasonably sure that modern humans and primates are both related to the same common ancestor, there is constant debate over what initially caused the two species to split into early hominids and apes. According to some, our longest and most popular theory on the division of man and ape is profoundly wrong. However, those same individuals usually offer an equally controversial theory as a substitute, one that is almost impossible to scientifically test or prove. Both the Savanna Theory and the Aquatic Ape Theory offer solutions to how and why humans evolved into bipedal toolmakers. But with enough questioning, each loses its accountability to rhetorical science.
As archeological discoveries of bone fragments and fossils continue to support the existence of homo-sapiens
The Early Years Foundation Stage (EYFS) curriculum in England differs greatly in structure and content to the Te Whariki curriculum in New Zealand; this therefore makes for an interesting comparison. The EYFS was introduced in England, in 2008, by the DfE as a framework that ‘sets the standards for learning, development and care of children from birth to five’ (DfE, 2012). Alternatively, Te Whariki was founded in New Zealand, in 1996, based on the aspirations for children ‘to grow up as competent and confident learners and communicators, healthy in mind, body, and spirit, secure in their sense of belonging and in the knowledge that they make a valued contribution to society’ (Ministry of Education, 1996). Throughout this essay, the EYFS and Te Whariki curriculums will be compared and contrasted to give a greater understanding of the similarities and differences between England and New Zealand regarding their beliefs about young children’s needs.
Darwin's General Summary and Conclusions of the Descent of Man and Selection in Relation to Sex In the "General Summary and Conclusions" of The Descent of Man, and
From the ancient bones of the Neanderthals, scientists have been able to extract small amounts of DNA. The DNA comparisons to modern humans show no relationship, implying evolutionary separation (Kunzig, 159). Some anthropologists say the small sections of DNA found are not conclusive evidence, because modern humans show just as much variation in DNA. These people point out that individuals such as the “Portugal Kid” are hybrids of Neanderthals and modern humans, showing there was gene trading. One argument against this is that there is no skull from the ‘Portugal Kid” so it is hard to compare it to Neanderthals. Also, it is known that closely related species can breed and their offspring can be fertile, but they are still separate species (Kunzig, 161).
Our technology is not yet strong enough to rule out both sexes as carriers of common genes. Therefore, the case of interbreeding still remains to be closed. However, Paabo and his team are confident that their research has proved that Neanderthals could not have died out solely because of interbreeding. Scientists are still trying to conclude what exactly the Neanderthals did; this discovery brings them one step closer, but not completely to the edge. Source All references and resources are taken from the Public Library of Science, Biology March 2004 issue and from Science March 16, 2004.
Humanity became fascinated with the idea of evolution with the work of Charles Darwin and the Scientific Revolution. People began hunting for fossils that would prove that man had an ape derived ancestry (Weiner, 1955). After various years of searching, a piece of physical evidence was found in England that was said to confirm the theory of evolution (Weiner, 1955).This confirmation came from Charles Dawson’s discoveries from 1908, that were announced publicly in 1912 (Thackeray, 2011). Dawson was believed to have found the fossil remains of the “missing link” between ape and human evolution, the reconstructed skull of Piltdown man (Augustine, 2006). The material was found in stratigraphical evidence and animal remains that were, at the time, adequate enough to confirm the antiquity of the remains (Weiner, 1955). In 1915, another specimen, Piltdown man II, was found further proving this theory (Augustine, 2006). However, this was merely a hoax proven by fluorine relative dating in 1953; the artifacts and bone fragments discovered turned out to be altered to fit the proposed scenario (Augustine, 2006). The skull found was actually composed of a human braincase that was younger than the complimentary orangutan lower jaw (Falk, 2011). Both sections of the skull had been stained to appear to be from the same person of the same age (Falk, 2011).The perpetrator of this act was never caught and there are many theories proposed for the motive of this hoax (Augustine, 2006). Many people have been taken into consideration for this crime, such as Chardin, Woodward, Hinton, and Dawson (Augustine, 2006). Nevertheless, the evidence that proves that Dawson is guilty of this crime against anthropology is quite substantial compared to the evidence...
Paleoanthropology: Pliocene and Pleistocene Human Evolution. Paleobiology, 7:3:298-305. Frayer, David W. and Milford Walpoff 1985 Sexual Dimorphism. Annual Review of Anthropology, 14:429-473 Key, Catherine A. 2000 The Evolution of Human Life History.
Sensationalism is described as “use of shocking material: the practice of emphasizing the most lurid, shocking, and emotive aspects of something under discussion or investigation, especially by the media” (“Sensationalism”, 2009). This has tactic has been used for ages. Whether it’s stories being told about a monster who will eat bad children, to the dangerous communist ways, sensationalism is everywhere. Sensationalism began during the era of Pulitzer and Hearst newspaper era. Their feud would introduce sensationalism to media, and impact the lives of many.
According to Britannica Encyclopædia, Australopithecus anamensis lived in Kenya between 4.2 million and 3.9 million years ago. A. afarensis lived in eastern Africa between 3 and 4 million years ago. This australopithecine had a brain size a little larger than chimpanzees. Some had canine teeth more sticking out than those of later hominines. No tools of any kind have been found with A. afarensis fossils.
The primary explanation for the differences in how people express their emotions rests on biology. First of all, our biological sex is the best predictor of the ability to detect and interpret emotional expressions (Swenson & Casmir, 1998). Our gender can shape how receptive we are of other people’s feelings, whether that person is of the same or different sex as us. Usually, people are generally better at recognizing the emotions of the member of the same sex (Adler, Rosenfeld, Proctor, 2007). The definition of being a man or a woman is also influenced by the culture one grows up in. Typically, most boys are taught to be tough even at a young age and are even encouraged by most fathers to play roughly with other boys their age. Crying is one emotion that is greatly discouraged because it is seen as a sign of weakness. On the contrary, it is acceptable for girls since society teaches them to be gentle and nurturing. This probably explains why males are usually more aggressive and competitive than females. These also go hand in hand with the social roles of men and women in society. Our occupations can also get in the way of expressing our emotions, as we are expected to act pleasant even though we don’t really feel that way. For example, ...
This literacy review aims to discuss why it is important for teachers to maintain responsive and reciprocal relationships with the parents and whānau of their students. The three articles that will be reviewed and synthesised are Collaborating with Parents/Caregivers and Whānau (Fraser, 2005), Successful Home-School Partnerships: Report to the Ministry of Education (Bull, Brooking & Campbell, 2008) and Strengthening Responsive and Reciprocal Relationships in a Whānau Tangata Centre: An action research project (Clarkin-Phillips & Carr, 2009). The review will focus specifically on the discussions about parent-teacher partnerships within said articles. The key findings within the literature will be examined and related to contemporary theorists. This review will also discuss why we need these partnerships, the child’s perspective on these relationships, the impact of the parent’s perspective on development and specific issues that may be encountered.
Homo erectus is also known for its larger body compared to earlier ancestors. "Past estimates of Homo erectus stature frequently were in the 5-5 1/2 feet (152-168 cm) range for adult males and arou...
For many eons the roots of kaupapa Māori theory have grown in Aotearoa by virtue of being the Māori ideology: a philosophical doctrine, incorporating the knowledge, skills, attitudes and values of Māori society; whereas critical theory was developed in the “Frankfurt School “in Europe, in the 1930s. But apart from those thousands of miles and years, they have surprising similarities to each other (Pihama, 2001). Nonetheless: kaupapa Māori theory is defined by Māori for Māori (Pihama, 2001). With a similar process, but not in a Māori context, critical thinking analytically questions what is normally recognised as the unquestionable truth and evaluates it before reconstructing it (Elder, 2007). One vital aspect in the relevance to education of critical theory and kaupapa Māori theory is the importance of teachers creating positive learning environments (Ministry of Education, 2010). Contrasting this, an example as defined in the Te Kotahitanga report, is the deficit theory, where mainstream teachers blame the lack of Māori educational achievement on the students themselves, or their families or cultural background (Ministry of Education, 2010). The consequence of this deficit theorising is probable failure of pupils in the school system. Discussed in this essay will be the deficit theory and why education needs to look towards the more positive models of the kaupapa Māori theory and critical theory with their similarities and successes.