Altruistic behaviour has prevailed for hundreds of years in both humans and animals. It is a peculiar concept which intrigues many in the scientific and psychology communities especially as the act of benevolence directly contrasts Darwin’s evolutionary theory (Darwin, 1859) (1) and Herbert Spencer’s interpretation of it when he coined the phrase ‘survival of the fittest’ (Spencer, 1864)(2). The mere thought that an animal would participate in an activity that will benefit others but in no way themselves is remarkable. And this act of kindness is demonstrated by a wide range of taxa varying from mammals to invertebrate almost none of which are compensated in return for their courtesy.

The word altruism was coined/popularised in 1830’s by French philosopher Auguste Comte and it describes the group phenomenon, which evolves by group selection, instead of the more traditional individual selection (Darligton, 1977) (3). There are multiple scientific definitions of altruism, a good one being psychological altruism which is where an individual, regardless of its own benefit will carry out a behaviour with consideration of another individuals welfare (Taylor, 2010). Simply put altruism is the selfless concern for the well being of others, it requires at least a group of two, an altruist that pays the cost and a recipient that receives the benefit. 

A model produced by Wilson demonstrated that animals living in smaller areas than the could in other words animals that have not gone through their dispersal phase yet for example a tadpole before its metamorphosis will prefer altruistic traits of fitness traits as they are limited in their house and it may be deemed a safer investment (Wilson, 1975) (4).

Altruism comes in two forms; kin altruism, which is a form of altruism where the altruistic individual has an interest in the welfare of the receiver, as it will increase the altruists fitness and therefore the chance of their genes being passed on. A good example of this would be a parental figure such as a mother seagull feeding her young. This process will come at a cost to the altruist however they will *unknowingly* deem it to be a good investment of energy and resources as the survival of the offspring is in their best interest. Because the offspring will contribute to the fitness of the altruist through the passing on off there genes. (Hamilton, 1964) (5)

The other type of altruism is reciprocal altruism,  which is use by biologists to explain cooperation that cannot be accounted for by kin selection.

Kin altruism is supported by more by biologist, as they will generally only use reciprocal altruism to explain any interactions that look like more than one animal are co-operating when kin selection doesn’t apply for example David Attenborough 

The theory of altruism in an economical sense suggests that egotism and selfish actions, will often trigger altruistic behaviour. Meaning an egotistic action will stimulate an animal to act altruistically this concept was produced (Twemlow, 2005).

The theory of evolution was produced by Darwin during the mid 19th century, he formed the scientific theory of natural selection which basically states that heritable traits that improve an organisms chance of survival are chosen over traits that will decrease the chances of the serval of that organism.

 Darwin stated after reflecting on the similarity of organism, that each species had not been made separately, and in fact that they had originated from other species. 

We were able to see evolution in action from evidence provided by fossil records which enabled us to make comparisons between the species we have nowadays to those found in the fossils. Oxford dictionary of animal behaviour

However, even Darwin struggled with the concept of altruism and saw it as a glitch in his evolutionary theory as the two ideas directly contrast with each other. 

Honeybee’s are a great example of altruism and are in fact one of the most extreme cases. Known as eusociality, individuals within the hive will give up reproducing in order to care for the young of another, which in this case is the queens offspring.

Darwin found it difficult to explain why a system like natural selection, which would reward individuals for reproducing, would create individuals that did not reproduce. And naturally, you would expect for these individuals, that improve the fitness of others at the expanse of their own, to be weeded out through the process of natural selection, however, the bees have one of the most well organised social systems in the animal kingdom.

Altruistic behaviour contradicts Darwin’s theory as he proclaimed that the most selfish animals are the best survivors (Darwin, 1859). 

From the point of view of evolution, which is simply the believe that the organisms we recognise today have developed from earlier forms, this behaviour is complex, in theory an organism that maximises its own fitness should be in a better condition and therefore more capable to endow its genes than an individual that is altruistic and sacrifices its fitness for that of others. If this was the case, the process of natural selection should highlight the good samaritans  and leave only individualists, nevertheless, altruistic behaviour still exists, (Lamb, 2016)

Organisms will only participate in activities that use energy if the cost of it is outweighed by the rewards hence why the altruistic behaviour is so interesting, as it demands a lot of energy to be invested (the cost) and provides no profits (the reward) for the altruistic individual. This leads one to wonder what its real benefits are. An intriguing question that arrises from this information is what is the reward, one feasibility is to regard the cost to the altruist and the benefit to the recipient as being measured in units of fitness. If this is taken in to account the definition of altruism can be altered and in consequence parental care does not qualify as altruism because through the individual caring for it’s young, it will also be increasing its own fitness as there is an increase in the likelihood of the offspring’s survival. (oxford dictionary of animal behaviour). According to the kin selection theory, altruistic individuals would prevail because the genes that they shared with their kin would be passed on. Since the whole clan is included in the genetic victory of a few, the phenomenon of beneficial altruism came to be known as “inclusive fitness.” By the 1990s this had become a core concept of biology, sociology, even pop psychology.

 
An interesting example of altruism which was described by Juliet Lamb was seen in the common vampire bat, Desmodus rotundus. After sneaking up on a sleeping cow and consuming enough of its blood to increase her body weight by 50% a female bat returns back to the nest. Upon arriving at the tree which she shares with a group of other female bats, she finds that one of the other bats in her roost hasn’t been so lucky. For the second night in a row, this other female has failed to feed, and she is close to starving to death. The returning bat sidles over to her and offers her a regurgitated mouthful of her own hard-earned blood meal. Both of them will live to bite another day. This is a great example of altruism as it benefits the returning female in no way to share her findings however she does it anyway, one benefit the returning female will get from this is that the two bats maybe related so through helping the other bat she will be increasing the chance of her genetic material being passed on. However, when this study was carried out it was not known if the bats in the lightning were related so this could be a true act of kinder that the retiring bat performed in order to save the others life. 

Another interesting sighting of altruism took place in the woods of New England when Bernd Heinrich was on a hike, he observed something which would go on to change our perception of animal psychology. A group of ravens had gathered to feed on a dead moose. But rather than choosing to keep the bounty for themselves, they were making a strange call, one which seemed to be deliberately attracting more ravens to the feast. Heinrich the biologist at the University of Vermont, was initially confused. By helping their competitors, the Ravens appeared to be defying all natural biological instinct. But as it transpired, their motivation was actually deeply selfish. The birds were juveniles who had discovered the moose in an adult raven’s territory. By inviting other ravens to join them, their intrusion was more likely to go unchallenged. So from an act of egotism came and an act of altruism.

Darwin’s evolutionary theory directly contrasts the action of altruism that many organisms show in their behaviour. Through the multiple definitions of altruism we can confirm it is the action of an altruistic individual paying a cost and in return receiving no reward for example a mother feeding her young. The mothers does not gain any of the nutritional benefit from the food and will have potentially had to use a great deal of resources and energy to gather it for her young making the costs heavily outweigh the rewards. Leading one to wonder what the reason for participating in such an action is, through my research in the matter I have concluded that it could be down to a combination of the following points, that overall it will benefit the altruistic individual as increases their fitness, in the case of a mother and young the mothers fitness will increase if she helps her young as there is a higher chance of her genes being passed on in the future. The other factor that could contribute to the reason for an individual acting altruistically could be that it is ingrained already in their behaviour and it is their nature to act in this way. Along with some influence from other members in a group all of these components could contribute to an animals likelihood of acting altruistically.