Biological Behavior of Altruism

The selfless act of the aliens made me think of the biological behavior of altruism. Altruism is an action that is costly to the organism that performs it but is beneficial to the other organism (West et al.

, 2007). West indicated differences between reciprocal and week altruism. Reciprocal altruism takes place between nonrelatives and happens when individuals take turns helping each other. This is termed “reciprocal” because the individual with favor helping an individual that has helped them in the past. It is not completely altruistic however, because there is a direct benefit to cooperation, thus making it mutually beneficial (West et al., 2006).

A behavior is weakly altruistic if it leads to a fitness reduction of the primary individual, comparative to the others. “Whole-group” or “group beneficial” traits are the ones that benefit the group and the individual performing it; however, “other-only” traits are ones where the individual does not benefit. Whole group traits can be considered a direct or indirect benefit, but this depends on the cost and benefit of the individual as well as the population structure (West et al., 2006). There are different examples of this found within the animal kingdom but frequently in species with complex social structures (Okasha, 2013)

One example that was researched by a group of scientists is between humpback whales and killer whales. Killer whales are known mammal eating predators and have attacked humpback whales. Previous research has concluded that humpback whales are just display defensive behaviors against the killer whales, but Robert Pitman and his team have showed that they are intentionally interfering attacks on other humpbacks and other species (Pitman et al., 2017). Humpbacks were approaching mostly mammal-eating forms of killer whales and some of the distance traveled was extremely significant. The reaction of the humpbacks was the same independent of what species approached the other, meaning the same behaviors were used defensively and offensively (Pitman et al., 2016). The most common behaviors of the humpbacks were slapping their flukes or splashing them, bellowing, pursuing behavior, and flipper slapping. The pursuing behavior consisted of following, chasing, charging at the killer whales. 31 out of 56 times, the humpback whales used these behaviors offensively against the killer whales. The approaching of the humpbacks had some effect on the outcome of attacks and it was reported that they were responsible for the escape of some of the prey. Pitman found that out of the five attacks involving the prey being other humpbacks, the approaching of the humpbacks made four of the attacks unsuccessful and the conclusion of the last was unknown (Pitman et al., 2016).

In some cases, the humpbacks were seen to come to the aid or defense of the victims and even drove off the aggressors. Observers have stated that the prey can escape with the help of humpbacks because they distract the killer whales. Another example of altruism can be found in vampire bats. Brian K. McNab discovered regurgitation in bats when doing research at the University of Florida. The bat will die if it does not eat within 60 hours because it cannot maintain the required body temperature. To keep their bodily functions operating properly, bats need to consume between 50 to 100 percent of their body weight in blood a night. Feeding is a difficult task, especially for young bats.

In the 1970’s a zoologist named Uwe Schmidt discovered evidence that female bats regurgitate blood for their babies. He discovered that soon after their birth, the pups would take regurgitated blood and milk from their mothers and in some instances would even take blood from other adults (Wilkinson, 1990). The findings of Schmidt made Wilkinson interesting in doing his own research on the regurgitation of vampire bats. He wanted to see if bats were only feeding their relatives or if they were reciprocally exchanging food. Over the five years of research, 110 instances of blood sharing through regurgitation were witnessed. 70 percent of these events were mother bats feeding their pups and thus are considered parental care.

The other events consisted of mother bats feeding other pups, females feeding other adult females, and males feeding their offspring. Through this experiment, Wilkinson found that the bats do not share blood randomly but share mostly with frequent roost mates and with relatives. This finding supports both reciprocity and kin-selection theories. In another experiment conducted by Wilkinson, he tested reciprocity and found that blood sharing mostly took place between bats of the same population. Furthermore, he found that blood sharing was not random and that the bats seemed to form a buddy system, where two bats would almost exclusively regurgitate for one another, this indicates that they must often have to reverse roles. Wilkinson also conducted another experiment with Carter. In this experiment, he found that blood sharing only occurred between females. Sixty three of 98 dyads that shared food had relatedness of 0.05 percent. This percentage of 64 percent is close to the expected percentage of 67 if partners were chosen at random with respect to relativeness (Carter and Wilkinson, 2013).

In each trial, receivers were fed by an average of 3.9 donors and the minimum donation time was 191 seconds. The total amount of food received from all contributors was about five percent of the recipient’s mass, this restored approximately 20 percent of the mass lost during the 24-hour fasting period. Based on his data, the relationship between food donated and received increased in slope with higher relatedness. Food received, donor sex, and allogrooming received also predicted presence of food sharing. No evidence was found to support ferocity because being fed did not cause in increase in subsequent food sharing. Wilkinson and his team found a correlation among captive bats where co-roosting association is held constant, the predictive role of reciprocal help exceeds that of relatedness. Food received from a partner was the strongest predictor of the presence If and amount of food donated. Stephens tried to model altruism in guppies and baboons. A couple guppies will swim away from their school to inspect a predator and gain knowledge about the likelihood of an attack. If the guppy approaches the predator, if has a higher chance of getting eaten but it also has a higher chance of gaining knowledge about the predator. If the guppies inspect together, each guppy has a lower chance of getting eaten and thus the school can still get informed. The cooperation between the guppies is simultaneous (Stephens, 1996).

In a previous experiment, the test fish moved closer to the predator when the control fish seemed to be closer to the predator. If the control fish did not move closer to the predator, neither would the test fish. The test fish’s behavior is compatible with a Tit-for-Tat strategy. For the guppies, the risk of being eaten or injured must be relatively low compared to the gain of information. In a different experiment that involved baboons, one olive baboon will sometimes implore help from another male in fighting a rival over a female. This is characterized as a two-by-two game because the one male can choose if he wants to help or not and is at risk if he does, while the other male can gain access to the female. The reciprocal is not simultaneous because only one baboon experiences a benefit (Stephens, 1996).

Dolphins have also been thought to have altruistic behaviors. The most suggested model to study altruism in dolphins is nondiscriminatory nepotism and it refers to the observation of epimeletic behavior. Behavior is typified more by learning than by innate patterns. They are very flexible and are capable of second-order learning. Epimeletic behavior is performed in response to new situations. Dolphin altruism is best studied using a multiparty model and these behaviors can be identified as friendships between dolphins. When dolphins can swim in a group, they feel secure because they can get help if needed. When mutual dependence increases, so does the cost and benefits of their interactions with other because individuals can no longer provide for themselves. The data on school structure shows fluidity in relationship and intergenic and interspecific cooperation is present. Reciprocity allows for the development of complex social relationships (Connor and Norris, 1982). As one can see, altruism is found in many different species. Altruism can exist in different ways based on who benefits from the interaction. True altruism can be difficult to find but with the right criteria, it can be found. It has been researched for many years to help get a better understanding of why an organism would risk their life for another. It is still not completely known why this occurs, but different animals do it for different reasons. This is done when the benefit outweighs the cost.

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