Recently, when a group of sperm whales about a thousand miles off the coast of Lisbon, Portugal, took in an adult bottlenose dolphin, behavioral ecologists were puzzled.
While cross-species interactions are not uncommon among terrestrial animals, sperm whales are not known for forging nurturing bonds with other species. Such an alliance had never been witnessed before. For eight days, the dolphin traveled, foraged and played with the adult whales and their calves. When it rubbed its body against the whales, they would sometimes even return the gesture.
What makes this story even more fascinating is that the dolphin had an S-shaped, spinal deformity. Apparently, there was no benefit to the whales of forming this bond with the handicapped dolphin.
Could this be evidence that animal altruism is real? A bottlenose dolphin in New Zealand once rescued two beached whales, leading them into deeper waters. Some wildlife researchers believe that altruism—defined as an act in which an animal sacrifices its own well-being for the benefit of another animal—is a well-documented behavior.
Those who say animal altruism exists cite examples such as dolphins helping others in need or a leopard caring for a baby baboon. In fact, in , a bottlenose dolphin came to the rescue of two beached whales in New Zealand and led them into safe waters. In another incident in New Zealand , a group of swimmers were first surprised when dolphins began circling around them, tighter and tighter, splashing in the water. The swimmers initially thought the dolphins were displaying aggressive behavior, but it turned out that they were warding off sharks.
That could have made the animal more likely to initiate an interaction with the large and slower-moving whales. The whales alternate their dives, always leaving one adult near the surface to watch the juveniles. The presence of the calves, which cannot dive very deep or for very long, allowed the dolphin to maintain contact.
Marine biologist John Francis, vice president for research, conservation and exploration at the National Geographic Society, however, postulated that the whales could just be satisfying a desire for the company of other animals.
Some species of whales have been known to display a desire for the company of other animals—such as humans. Animals are only altruistic when it promotes their survival. For example, a cuckoo bird will lay an egg in the nest of a host bird of another species, usually one with similar-looking eggs to its own. The host bird then looks after the egg as if it were its true offspring. If their young are still there, they will leave the nests alone.
Bernd Heinrich, a biology professor at the University of Vermont, was hiking through the Maine woods one day when he happened upon a group of ravens feasting on a dead moose.
They were unusually noisy and making a loud call that Heinrich had never heard before—a call that seemed to attract even more ravens to the scene. The behavior stymied Heinrich, because, in his view, ecological theory stipulates that a food bonanza should be defended, not shared. But the birds were sharing—to the point that some of the ravens even returned to their roost to recruit more birds. This odd incident inspired Heinrich to conduct a series of field studies, which he eventually published in the book Ravens in Winter But like most examples of animal altruism, what seemed to be a selfless act had selfish benefits.
By bringing other young ravens to the feast, they avoided being chased off by the territory-holding bird. Stevens believes that for any behavior to survive natural selection, it needs to help an animal or its genetic material. Do you think that animals are capable of true altruism?
Twitter - Facebook. Clearly these cases cited of altruistic behaviour by animals offer no chance of reciprocity other than perhaps a good feeling about doing it. We are unique in our level of consciousness and our advanced ability to construct mental structures to introspect but it is likely that we are not creators or founders of morality; instead jut the most expressive reflective articulators of it.
Likely, there are extraterrestrial creatures in the universe that we have not yet met that have arrived at a deeper consciousness than we have currently. Our level of consciousness is more a product of genetic drift than through natural selection and other creatures will develop it eventually, if we spare the world for them to do so.
Altruism exists in mammals and birds mostly. This stems from empathy. The point of empathy is to make the self and another indistinguishable. We feel pleasure at helping others. Semantics are the problem. If doing something for another is just as selfish as helping oneself, language has become obsolete. We humans are vain. There have been numerous sightings by researchers while aboard vessels conducting unrelated research, of whales saving the lives of young seal.
Rolling onto her back a whale may draw an imperiled seal pup onto her belly, where the pup rests secure till the predator, in the report I read, a shark, had withdrawn. The pup then slid into the water and made for the icefloes and its mother.
Allomaternal care. Key word any animal. I found related behaviour among Ravens. Allomaternal care is common among birds. In mammals, some form of alloparenting has been reported in over species. They will cooperate to lift a fallen family member. Natural phenomena, aninal interactions and behavioural aspects are as diverse amd mysterious as nature itself.
Meaning the behavioural triats of humans are as diverse as the number of human beings — each is different from others in certain respect. Therefore, may it be altruism, agonastic, parasitic, or other type of behaviour we know some but do no know many that could be known in due course of time.
Animals behaving in normal circumstances do often behave differently in altered circumstances. I believe altruism is true and almost universal in human, domesticated and wild animals. We need to observe more intricately to gather more information. Carolina covers the world of life science with everything from slides and kits to Agricultural and Vet Science. We have kits for new and traditional AP Biology labs. Choose from our kits, follow a college board lab, or design your own with our wide variety of equipment and supplies.
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We see frequent examples of self-sacrifice by humans, in both professional and spontaneous capacities. What about self-sacrifice among other animals? Evolutionary biologists and animal behaviorists study such behaviors, looking for both immediate and evolutionary explanations. Rationales for self-sacrificing behavior are discussed and debated across the fields of animal behavior, evolution, ecology, psychology, and philosophy.
Biological altruism presents an evolutionary puzzle. If individuals act under the pressures of self-preservation and the desire to reproduce, then why would 1 organism help another, putting its own reproductive success at risk?
Further, if the tendency toward altruism is a heritable trait and individuals with the trait are less reproductively successful, then why is the frequency of altruism relatively high? Before getting into the changing views of altruism, I will present 3 often-cited examples from altruism research. They may serve as case studies and topics of further research for your class. Vampire bats are long-lived, social animals that feed during the night and return to their group for daytime roosting.
Researchers tagged each bat for identification. The bats can survive only 2 or 3 days without feeding. The dispute between those who regard weak altruism as individually advantageous, and those like Wilson who regard it as group advantageous, stems ultimately from differing conceptions of individual and group selection. For Wilson, individual selection means within-group selection, so to determine which strategy is favoured by individual selection, one must compare the fitnesses of W and N types within a group, or pair.
For other theorists, individual selection means selection based on differences in individual phenotype, rather than social context; so to determine which strategy is favoured by individual selection, one must compare the fitnesses of W and N types in the same social context, i.
These two comparisons yield different answers to the question of whether weak altruism is individually advantageous. Thus the debate over how to classify weak altruism is intimately connected to the broader levels of selection question; see Nunney , Okasha , , Fletcher and Doebeli , West et al. A further source of ambiguity in the definition of biological altruism concerns the time-scale over which fitness is measured.
Conceivably, an animal might engage in a social behaviour which benefits another and reduces its own absolute fitness in the short-term; however, in the long-term, the behaviour might be to the animal's advantage. So if we focus on short-term fitness effects, the behaviour will seem altruistic; but if we focus on lifetime fitness, the behaviour will seem selfish—the animal's lifetime fitness would be reduced if it did not perform the behaviour.
Why might a social behaviour reduce an animal's short-term fitness but boost its lifetime fitness? Sachs et al. By performing the behaviour, and suffering the short-term cost, the animal thus ensures or raises the chance that it will receive return benefits in the future. Similarly, in symbioses between members of different species, it may pay an organism to sacrifice resources for the benefit of a symbiont with which it has a long-term relationship, as its long-term welfare may be heavily dependent on the symbiont's welfare.
From a theoretical point of view, the most satisfactory resolution of this ambiguity is to use lifetime fitness as the relevant parameter cf. West et al. This stipulation makes sense, since it preserves the key idea that the evolution of altruism requires statistical association between donor and recipient; this would not be true if short-term fitness were used to define altruism, for behaviours which reduce short-term fitness but boost lifetime fitness can evolve with no component of kin selection, or donor-recipient correlation.
The theory of reciprocal altruism was originally developed by Trivers , as an attempt to explain cases of apparent altruism among unrelated organisms, including members of different species. Clearly, kin selection cannot help explain altruism among non-relatives. Trivers' basic idea was straightforward: it may pay an organism to help another, if there is an expectation of the favour being returned in the future.
The cost of helping is offset by the likelihood of the return benefit, permitting the behaviour to evolve by natural selection. For reciprocal altruism to work, there is no need for the two individuals to be relatives, nor even to be members of the same species. However, it is necessary that individuals should interact with each more than once, and have the ability to recognize other individuals with whom they have interacted in the past. This evolutionary mechanism is most likely to work where animals live in relatively small groups, increasing the likelihood of multiple encounters.
Where reciprocal altruism is referred to below, it should be remembered that the behaviours in question are only altruistic in the short-term. The concept of reciprocal altruism is closely related to the Tit-for-Tat strategy in the iterated Prisoner's Dilemma IPD from game theory. In the IPD, players interact on multiple occasions, and are able to adjust their behaviour depending on what their opponent has done in previous rounds.
There are two possible strategies, co-operate and defect; the payoff matrix per interaction is as in section 2. The fact that the game is iterated rather than one-shot obviously changes the optimal course of action; defecting is no longer necessarily the best option, so long as the probability of subsequent encounters is sufficiently high.
In their famous computer tournament in which a large number of strategies were pitted against each other in the IPD, Axelrod and Hamilton found that the Tit-for-Tat strategy yielded the highest payoff.
In Tit-For-Tat, a player follows two basic rules: i on the first encounter, cooperate; ii on subsequent encounters, do what your opponent did on the previous encounter. The success of Tit-for-Tat was widely taken to confirm the idea that with multiple encounters, natural selection could favour social behaviours that entail a short-term fitness cost.
Subsequent work in evolutionary game theory, much of it inspired by Axelrod and Hamilton's ideas, has confirmed that repeated games permit the evolution of social behaviours that cannot evolve in one-shot situations cf. Nowak ; this is closely related to the so-called 'folk theorem' of repeated game theory in economics cf.
Bowles and Gintis For a useful discussion of social behaviour that evolves via reciprocation of benefits, see Sachs et al. Despite the attention paid to reciprocal altruism by theoreticians, clear-cut empirical examples in non-human animals are relatively few Hammerstein , Sachs et al.
This is probably because the pre-conditions for reciprocal altruism to evolve- multiple encounters and individual recognition—are not especially common. It is quite common for a vampire bat to fail to feed on a given night.
This is potentially fatal, for bats die if they go without food for more than a couple of days. On any given night, bats donate blood by regurgitation to other members of their group who have failed to feed, thus saving them from starvation. Since vampire bats live in small groups and associate with each other over long periods of time, the preconditions for reciprocal altruism are likely to be met.
Wilkinson and his colleagues' studies showed that bats tended to share food with their close associates, and were more likely to share with others that had recently shared with them. These findings appear to accord with reciprocal altruism theory. Trivers describes an apparent case of reciprocal altruism between non con-specifics. The interaction is mutually beneficial—the large fish gets cleaned and the cleaner gets fed.
However, Trivers notes that the large fish sometimes appear to behave altruistically towards the cleaners. If a large fish is attacked by a predator while it has a cleaner in its mouth, then it waits for the cleaner to leave before fleeing the predator, rather than swallowing the cleaner and fleeing immediately. Trivers explains the larger fish's behaviour in terms of reciprocal altruism.
Since the large fish often returns to the same cleaner many times over, it pays to look after the cleaner's welfare, i. So the larger fish allows the cleaner to escape, because there is an expectation of return benefit—getting cleaned again in the future. As in the case of the vampire bats, it is because the large fish and the cleaner interact more than once that the behaviour can evolve. The evolutionary theories described above, in particular kin selection, go a long way towards reconciling the existence of altruism in nature with Darwinian principles.
The grounds for this view are easy to see. Ordinarily we think of altruistic actions as disinterested, done with the interests of the recipient, rather than our own interests, in mind. But kin selection theory explains altruistic behaviour as a clever strategy devised by selfish genes as a way of increasing their representation in the gene-pool, at the expense of other genes. This is a tempting line of argument. Indeed Trivers and, arguably, Dawkins were themselves tempted by it.
But it should not convince. The key point to remember is that biological altruism cannot be equated with altruism in the everyday vernacular sense. Biological altruism is defined in terms of fitness consequences, not motivating intentions. Ants and termites, for example, presumably do not have conscious intentions, hence their behaviour cannot be done with the intention of promoting their own self-interest, nor the interests of others. Thus the assertion that the evolutionary theories reviewed above show that the altruism in nature is only apparent makes little sense.
As we have seen, the gene's-eye perspective is heuristically useful for understanding the evolution of altruistic behaviours, especially those that evolve by kin selection. Any evolutionary explanation of how a phenotypic trait evolves must ultimately show that the trait leads to an increase in frequency of the genes that code for it presuming the trait is transmitted genetically.
Do theories of the evolution of biological altruism apply to humans? This is part of the broader question of whether ideas about the evolution of animal behaviour can be extrapolated to humans, a question that fuelled the sociobiology controversy of the s and is still actively debated today cf.
Boyd and Richerson , Bowles and Gintis , Sterelny All biologists accept that Homo sapiens is an evolved species, and thus that general evolutionary principles apply to it. However, human behaviour is obviously influenced by culture to a far greater extent than that of other animals, and is often the product of conscious beliefs and desires though this does not necessarily mean that genetics has no influence.
Nonetheless, at least some human behaviour does seem to fit the predictions of the evolutionary theories reviewed above. In general, humans behave more altruistically in the biological sense towards their close kin than towards non-relatives, e. It is also true that we tend to help those who have helped us out in the past, just as reciprocal altruism theory would predict.
On the other hand, humans are unique in that we co-operate extensively with our non-kin; and more generally, numerous human behaviours seem anomalous from the point of view of biological fitness. Think for example of adoption.
Parents who adopt children instead of having their own reduce their biological fitness, obviously, so adoption is an altruistic behaviour. But it does not benefit kin—for parents are generally unrelated to the infants they adopt—and nor do the parents stand to gain much in the form of reciprocal benefits. So although evolutionary considerations can help us understand some human behaviours, they must be applied judiciously.
What is the relationship between these two concepts? They appear to be independent in both directions, as Elliott Sober has argued; see also Vromen and Clavien and Chapuisat An action performed with the conscious intention of helping another human being may not affect their biological fitness at all, so would not count as altruistic in the biological sense. Conversely, an action undertaken for purely self-interested reasons, i.
Sober argues that, even if we accept an evolutionary approach to human behaviour, there is no particular reason to think that evolution would have made humans into egoists rather than psychological altruists see also Schulz On the contrary, it is quite possible that natural selection would have favoured humans who genuinely do care about helping others, i.
Suppose there is an evolutionary advantage associated with taking good care of one's children—a quite plausible idea. Then, parents who really do care about their childrens' welfare, i. Contrary to what is often thought, an evolutionary approach to human behaviour does not imply that humans are likely to be motivated by self-interest alone.
Altruism and the Levels of Selection 2. Kin Selection and Inclusive Fitness 2. Conceptual Issues 3. Reciprocal Altruism 5. Altruism and the Levels of Selection The problem of altruism is intimately connected with questions about the level at which natural selection acts.
Kin Selection and Inclusive Fitness The basic idea of kin selection is simple. Player 2 Altruist Selfish Player 1 Altruist 11,11 0,20 Selfish 20,0 5,5 Payoffs for Player 1, Player 2 in units of reproductive fitness The question we are interested in is: which type will be favoured by selection? Conceptual Issues Altruism is a well understood topic in evolutionary biology; the theoretical ideas explained above have been extensively analysed, empirically confirmed, and are widely accepted.
The payoff matrix is thus: Player 2 Weak Altruist Non Player 1 Weak Altruist 30,30 10,20 Non 20,10 0,0 Payoffs for Player 1, Player 2 in units of reproductive fitness The payoff matrix highlights the fact that weak altruism is individually advantageous, and thus the oddity of thinking of it it as altruistic rather than selfish.
Reciprocal Altruism The theory of reciprocal altruism was originally developed by Trivers , as an attempt to explain cases of apparent altruism among unrelated organisms, including members of different species. Bibliography Abbot, P. Avital, E. Axelrod, R. Birch, J. Bowles, S. Boyd, R. Levinson and N. Enfield eds. Bourke, A. Carter, G. Clavien, C. Cronin, H. Darwin, C. Dawkins, R. Dugatkin, L. Fletcher, J.
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