This paper deals with two articles and two conversational scripts, each of which tries to emphasize the predominant role and the process of evolutionary development that dates back to our ancestors, and which cascades down to our own lives and plays a role in determining our current behavior and lifestyle.
The first article titled Potential Evolutionary Role for Same-Sex Attraction (Association for Psychological Science, 2010), published in the Science Daily on Feb 4, 2010, tries to highlight the role of human evolution in promoting homosexuality amongst men. The article -- based on the research findings of two evolutionary psychologists, Doug VanderLaan and Paul Vasey of the University of Lethbridge in Canada -- challenges the age-old thought process of blaming a person’s genetic architecture for making him gay. It holds the human evolutionary development -- in the form of the kin selection hypothesis -- responsible for same-sex partner preferences in males.
According the Kin Selection or Inclusive Fitness theory, the biological evolution of people supports their genetically close relatives based on the logic that the spread of human genes occur both when a person’s close relatives (kin) procreates and when the person initially carrying the genes procreates, since they both possess copies of the same genes. Applying this theory to homosexual males suggests that their display of altruism towards their younger nieces and nephews in the form of bearing their educational and medical expenses, buying gifts, and baby-sitting allows them to be helpers in the nest (Association for Psychological Science, 2010). This compensates for their childlessness and in the process, also enhances some of their own genetic prospects (Association for Psychological Science, 2010).
The second article titled Contact With Dads Drops When Women Ovulate: Evidence of Evolutionary Protection Against Inbreeding in Women? (University of California - Los Angeles, 2010) tried to offer an evolutionary explanation for lesser contact between women and their fathers during the ovulation period. The article -- based on the findings of a group of researchers at the University of California, Los Angles; University of Miami; and California State University, Fullerton -- employed the innovative use of cell phone records to describe a deliberate effort made by women to remain distant from their fathers while undergoing ovulation; thereby bringing an evolutionary angle of safety against inbreeding into it (University of California - Los Angeles, 2010). The researchers studied the cell phone call records of forty-eight women aged between 18-22 years old – considered the most fertile years – within one billing period where the calls were made to both their parents and where both the durations and dates of the calls were taken note of, together with the number of days every woman experienced low and high fertility during the same billing period (University of California - Los Angeles, 2010)
The results obtained indicated that the women called their fathers less frequently than they did their mothers during high-fertility periods as opposed to the low-fertility periods (University of California - Los Angeles, 2010). Further, in cases where they did call their parents, the results showed that call durations averaged at 1.7 minutes per day to their fathers during ovulation periods, compared to call durations that averaged at 4.7 minutes per day during the same ovulation period to their mothers (University of California - Los Angeles, 2010). In the same manner, during low-fertility periods, the same figures increased to 3.4 minutes per day for calls to the fathers during low-fertility periods, which would still be lower than the 4.2 minutes per day spent for calls to mothers (University of California - Los Angeles, 2010).
A notable point here is that in each case of father-daughter conversations, both the brevity of the call and the reluctance to speak much on the part of the daughters existed regardless of who dialed the number.
Commenting on the findings portraying weird father-daughter interactions, the researchers said that the absence of the call content made it difficult to pin-point the exact reason for such abnormal communications, although it might have stemmed from a hidden intention on the part of the women to avoid male interaction during high-fertility periods. This in turn can be caused by an underlying primitive urge to avoid inbreeding ─ an evolutionary adaptive defense mechanism at work. The basis for such an opinion would be the similar findings obtained in a previous research, which was conducted by evolutionary biologists where female animals were observed at a time when they were highly fertile. The study revealed identical behavioral patterns, that is, the animals kept a safe distance from their male relatives during that period so as to protect themselves against the negative outcomes of inbreeding like the long-term commitment of raising a child (University of California - Los Angeles, 2010) or the birth of unhealthy children, all of which occur when genetically close relatives mate.
This study only reiterated the findings of a large body of already existing research that confirmed that during women’s ovulation period, their sexual attraction towards males with a physique and personality associated with manliness grew manifold, especially when they have not had sex with such men before, although this all happened at an unconscious level. This is quite evident from their tendency to heavily indulge in behaviors that make them appear attractive and sexy to men during this time frame in contrast to a low fertility period. This includes everything from dressing up attractively to even altering their voice pitch to give it a sexual appeal. However, because they themselves are aware of the short fertility time frame at their disposal and the long-lasting unpleasant consequences of any wrong sexual decision taken due to their inability to control their libidos at this point of time, they avoid contact with male genetic relatives who are perceived as undesirable mates (University of California - Los Angeles, 2010). On the other hand, their increased interaction with the mothers takes place not only due to the absence of the risk of inbreeding but also because the mothers can be used as sounding boards for mating decisions as they are generally perceived to be more experienced (University of California - Los Angeles, 2010).
Finally, the paper also comprises of two conversational scripts, each of which tries to draw attention to the predominant role of early human evolutionary history in determining our contemporary habits and lifestyles. They are as follows:
Conversational Script 1
I helped a close friend at a party, who needed to know about evolution, on which he was to write an essay as part of a state-level essay writing competition to be held the following week. He needed the prize money to pay for part of the course fees for one of his semesters. Being a novice, with no knowledge about the subject at all, he did not want to get confused by the ocean of information on the Web. I gave him first-hand knowledge about the basics of evolution (Skelton, 1987) including the theory of evolution by natural selection, which forms the basis of evolution and then discussed the problems of survival. The conversation script describing basics of evolution is as follows:
My Friend: How did man evolve or in simple terms, develop?
Me: Human nature (mind and behavior) did not develop or evolve overnight. It was a long drawn process that took ages to get completed and is attributed to a series of psychological adaptations, i.e. changes taking place in a species over a period of time that serve as defense mechanisms enabling them to adapt to or survive in their environment. Evolutionary psychology is a sub-branch of psychology that scientifically studies the development of this human nature.
My Friend: Are these psychological adaptations responsible for the way we behave?
Me: Only those adaptations define and govern an organism’s or individual’s behavior that are favorable and promote survival, since as a result of being used repeatedly over a period of time they become an inseparable part of the individual’s psyche and personality and are also genetically inherited by the individual’s future generations through procreation.
My Friend: Can you offer any scientific explanation for all this?
Me: Yes, it is called the theory of evolution, propounded by Charles Darwin, who said that the earth has a wide variety of species, each having characteristics well-suited to achieve distinct functions. For example, spiders are able to spin webs unlike other insects. With time, they procreate to produce offspring that inherit their parents’ unique characteristics with slight variations, and also overburden the eco-system’s sustenance capacity. This results in a battle for survival, which is won only by those species that are naturally selected by the environment to survive, purely by virtue of the favorable variations in their genetic make-up, which they inherited from their parents, making them conducive to the changing environment; and thereby, promoting their survival. Numerous cycles of such genetic variations taking place generation by generation and cause the evolution of species through the creation of new species and modification/extinction of the old ones. For example, a lengthy study of passerine birds (finches) at Galapagos Islands revealed to Darwin that each bird had beaks of different lengths to perform a distinct function of procuring a specific type of food it ate for survival. Further, over the years, with each generation, the shape of the beak changed to accommodate all types of food. For example, in case of the unavailability of insects, the beak could be used to procure other foods also, like worms, grains etc.
My Friend: Finally, besides survival, what else does natural selection help in?
Me: Natural selection also helps in intersexual selection – traits that influence an individual’s choice for a sexual partner such as large breasts in females, as well as intrasexual selection ─ traits that facilitate competition between two same-sex members for access to an opposite sex member, such as males competing with each other for access to hot chicks!!
Conversational Script 2
Next we discussed problems of survival as follows:
My Friend: What survival problems do all living organisms face?
Me: All survival threats come from the following factors:
a. Physical environment ─ this includes one’s physical environment in the form of climate and weather. For example, people living in hot deserts have scorching days and chilly nights as survival challenges; whereas those living in extremely cold regions, face a different set of climatic challenges threatening survival.
b. Biological Factors ─ revolve around the diet of the organisms, which is necessary for survival and involves the consumption of sufficient amounts of calories and protection from toxins; thereby putting a premium on judicious food selection that is further shaped by food preferences& selection strategies for both man and animals developed through evolved psychological mechanisms (EPMs) such as taste preferences (sweet not bitter), felt needs (hunger & thirst), neophobia (fear of a new food item)and social transmission of food preferences. Last one shows a different pattern for both the species. Animals prefer novel foods based on their smell in the breath of other animals that ate it, in contrast to human beings, who choose new food items based on positive feedback received from others. Further, increased usage of spices in foods worldwide makes them microbe-free and safe to eat (Antimicrobial Hypothesis). People prefer ripe fruits that emit ethanol odor and are used to prepare alcohol ─ a by-product they like (Frugivory by-product hypothesis). Even meat evolved as a globally popular food due to its high nutrition value and “meat-friendly” human body architecture. People even tend to dislike particular food items because microbes contaminate them easily, leading to a fear of developing diseases (Disease-avoidance hypothesis). Finally, even pregnant women avoid caffeine, alcohol etc. for the fear of harming the fetus and developing pregnancy sickness (Embryo-protection hypothesis).
c. Psychological Factors ─ include fears, phobias & suicide as universally adaptive behaviors for escaping survival-threatening situations. Fears & phobias are unpleasant psychological states with physiological manifestations experienced in response to real and anticipated dangers, respectively. For example, fear of wild animals like tiger or claustrophobia, i.e. fear of closed places. Finally, suicide, despite nullifying classical fitness by killing an organism’s reproduction prospects, can still promote inclusive fitness. Inability to reproduce forces an organism to look after his kin. But, if unable to do so, despite his altruistic nature, it makes him more of a burden on them, thereby, causing him to commit suicide and propagate altruistic genes in them through a display of such model behavior in the form of his sacrifice that they will inherit and also pass on genetically.
Association for Psychological Science (2010, February 4). Potential evolutionary role for same-sex attraction. ScienceDaily. Retrieved from http://www.sciencedaily.com /releases/2010/02/100204144551.htm
Skelton, R. (1987). Charles Darwin and the theory of natural selection. Barron’s Educational Series: Hauppage, NY
University of California - Los Angeles (2010, November 29). Contact with dads drops when women ovulate: Evidence of evolutionary protection against inbreeding in women?.
ScienceDaily. Retrieved from http://www.sciencedaily.com