Lack of Hand Preference in Wild Hanuman Langurs (Presbytis Entellus) is a study that investigates handedness of different tasks across a natural population of Hanuman langurs. Manual specialization is the best indicator of the strong hemispherical lateralization the Hominidae are known for, clearly demonstrated by Homo sapiens who exhibit 90% right handedness. Researchers wanted to test whether the Hanuman langur demonstrated preference for either hand. They hypothesized that Hanuman langurs preferred their right hand during their completion of daily tasks.
For this study, researchers observed 10 randomly selected, free ranging, adult Hanuman langurs from the Siwalik mountains in southern Nepal. Of these ten, five of the Hanuman langurs were males, the other; female. Each of the females carried a non-weaned infant and all members were part of a multimale and multifemale, free-ranging group. Researchers watched these primates carry, eat, hit, hold, idle, manipulate, reach, retrieve, self-groom, and social groom. These primates were observed using a focal subject sampling in 20 minute sessions. Focal sampling is an observational technique in which the researchers focus and observe one individual at a time. During their observations, researchers recorded which hand the primates used to complete the specified tasks and the objects they interacted with.
The results revealed a lack of hand preference among the Hanuman langurs with an exception in the Eat category. Nine of the 10 subjects showed no statistically significant degree of lateralization. In the Eat category, five subjects displayed a preference for their right hand while four others showed preference for their left. Only one female demonstrated a significant prefer...
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...ing to learn more about the life around us, especially non-human primates. It is possible that some of the social patterns in the different primate communities may be prevalent in human social structure. This opens up more questions of why these social patterns are similar. Is the reason possibly biological? Sometimes there is no question to be answered and the only reason why research studies like these are conducted is simply because we are interested in knowing how a certain species of animals work.
Works Cited
Mittra, E. S., & Fuentes, A. A. (1997). Lack of hand preference in wild Hanuman langurs
(Presbytis entellus). American Journal Of Physical Anthropology, 103(4), 455.
Nikolei, J., & Borries, C. (1997). Sex differential behavior of immature Hanuman langurs
(presbytis entellus) in Ramnagar, South Nepal. International Journal Of Primatology, 18(3), 415.
This article, titled Common Ground, written by Barbara Smuts, points out the main differences between humans and apes, such as our upright stance, large brains, and capacity for spoken language and abstract reasoning. However, the main point of this article is to emphasize the many similarities that apes share with us. Smuts goes into great detail about how human social and emotional tendencies are very reflective in the family of apes.
While there are noticeable by differences in social conduct between these two primates, I argue that they are extra of similar behaviors than most books have suggested. This book portrays several reasons that modern views of bonobo and chimpanzee cultures may not harmonize well with ground data. Bonobos are derived since their behavior has been defined lately than that of chimpanzees, and the likelihood that explanations of bonobo-chimpanzee differences are echoes of human male-female alterations.
Our earliest ancestors are primates. They are our closest relatives which is why we can see our behavior’s and practices in them. If we observe them we can get a better understanding of them and us, human beings. But unfortunately we all don’t get the chance to see a Primate right in our backdoor. So the best thing I could do for my observation was to visit them at the zoo.
Hopkins, W. D., et al. "Handedness For Tool Use In Captive Chimpanzees (Pan Troglodytes): Sex Differences, Performance, Heritability And Comparison To The Wild." Behaviour 146.11 (2009): 1463. Publisher Provided Full Text Searching File. Web. 16 Apr. 2014.
It has been believed that culture is unique to humans and no other groups of animals have culture, but recent evidence refutes this ideology. Before getting into the meat of the argument, it is important to first address the issues regarding the ambiguity of the term, “culture.” What is culture? Many scientists may argue that culture is the way of life for a group of individuals, this definition includes the values, beliefs and traditions of the group (Sapolsky, 2006). Other scientists may argue that culture is the transmission of habits and information by social means (Sapolsky, 2006). Despite the different specifics of what culture is, almost all scientists would agree that culture is transmitted socially through social learning that promotes the transfer of information between members in a group (Boesch and Tomasello, 1998). Based on these notions of culture, it can be justifiably stated that primates have culture. Primates exhibit food preparation techniques, use of tools, communication skills, and most importantly, behaviors of social learning. An exemplar of primates’ capabilities for culture is Koko, the lowland gorilla. Koko, in captivity, was able to learn American sign language, demonstrate self-awareness and the ability to deceive.
108), however in the M-group, in Mahale, that the grooming hand-clasp appeared in at least one captive chimpanzee colony (Uehara, 2004, p. 108). The importance between the different types of hand-clasp grooming is crucial to determine the behaviors among cultures in primates. The objective was to test Mcgrew and colleagues’ idea that the palm-to-palm hand-clasp is custom of K-group and not of M-group (Uehara, 2004, p. 109). In some cases during the grooming the primates would stretch their arms and hold hands (palm-to-palm hand-clasp), but the primates also used other methods of grooming, such as stretching their arms and holding their wrists, or draping their arms over each other during the grooming process. (See images in (Uehara, 2004, p. 109). The study was to show whether or not those who used the grooming hand-clasp with three different partners demonstrated the same tendencies regardless of the partner (Uehara, 2004, p. 109). The results showed the majority of the K-group performed the palm-to-palm hand-clasps more often than M-group. During the observation, “the angle of the wrist in most cases concluded as either straight of flexed in approximately 91% of primates. In the Angle of
Being left handed or right handed is a natural development every individual catches on to at a certain age and according pediatrician (Laura Jana), most children start to show a preference for either their left or right hand at about 2 or 3 years old but can develop a preference as early as 18 months old. Most people feel that being right handed is an automatic adjustment that being right handed is correct and being left handed is viewed as a negative factor, in a retrospective study on decedents; scientist have solved the reason being that left handedness can reflect in a negative outcome. In researchers’ study (Marcel E. Salive, MD, MPH, and Jack M. Gurlnik, MD,PhD) they found that the average death rate for left-handers was 9 years lower
In his lecture, primatologist Robert Sapolsky explains the uniqueness of humans as well as our similarities to other primates. In doing so, he broke it down into six points of interest: aggression, theory of mind, the golden rule, empathy, pleasure in anticipation and gratification postponement, and lastly, culture. Professor Sapolsky approaches each point with interesting fact-based examples thus allowing me to gain insight on humans and other primates. Sapolsky’s knowledge of primates along with his scientific background allows him to make a clear argument that one cannot simply ignore.
Reaching into Thought: The Minds of the Great Apes, ed. A. E. Russon, K. A. Bard & S. T. Parker, pp. 257–77. Cambridge, UK: Cambridge University Press.
Humans and non-human primates have many behaviors and characteristics in common. All humans and non-human primates also share physical and beha...
Viewing and observing primates at the zoo and using them as a research subject is crucial to help with the understanding of how humans came to be. Since humans and primates are onwards of 95% genetically similar (Why are Humans Primates), observing them is a great tool to better understand humans and the relationship we share with primates. Though some research done on primates has questioned the morality of such a thing, by not observing our closest ancestors, we would not have many of the answers about humans that we have today. Non-human primates can teach us many things about ourselves, from evolution,to behavioral and social characteristics.
The purpose of this paper to examine the evolution of the human brain that distinguishes them from other species based on the traits that humans possess: such as language, emotional complexity and consciousness. The significance of traits are due to adaptations in humans to promote the survival of our ancestors. Professor Hamilton (2012) discusses that the evolution of the human brain starts with the idea of the Triune brain, proposed by MacLean, whereby the human brain is made up of three parts: Reptilian, Paleo-mammalian, and Neo-mammalian. Animals with the neo-mammalian brain have a more complex brain compared to the other parts, since this is where the neocortex evolved. Humans essentially have this higher brain function which is responsible for our ability to think, make decisions, promote agency, and the ability to relate with each other. This concept fits into the evolutionary process since it shows how the complex the brain has become through evolutionary processes. In essence, as humans, we “have a rich, evidence-based understanding of our behavior that can lead us to plan to be ‘better’ or ‘more successful’ people” according to Professor Hamilton (2012). Thus, shows how evolution plays a significance in understanding human behavior and comparing humans with other species.
Successful individuals come in all packages. What makes one person different from another does not define their victory in life. Do blonds have more fun than brunettes? Are blue eyed girls prettier than brown eyed girls? Are right-handers smarter than left-handers? Each of these questions above deal with being different and having that difference affect the success of the individual. Being left-handed is a blessing not a curse. Does a left-handed person have an advantage or a disadvantage? Left-handed folks are special. They have the ability to live in a world geared mainly toward right-handed members of society and flourish to great heights. It is proven that, on average, there is no significant difference in IQ between righties and lefties (Wang, 2011). Does being born left-handed create difficulties for success or does it prove to be a unique trait that can promote notable achievements? Even though such a small percentage of human beings in the population today possess left-handedness, this paper will show that being left-handed can and does create intelligent and creative people.
One of the most important and pivotal physical and biological adaptations that separate humans from other mammals is habitual bipedalism. According to Darwin, as restated by Daniel Lieberman, “It was bipedalism rather than big brains, language, or tool use that first set th...
Hand preference or handedness is the ability to use one hand more comfortably and skilled than the other hand for simple tasks such as writing or opening a door. A common belief that many people believe in, is the myth that left-handedness is a recessive gene and right-handedness is a dominant gene.