Interspecific Adoption: Can Evolution Explain Altruism in Animals?


Altruistic behavior is expected in humans to one extent or another. However, when animals behave altruistically, evolutionists are left without good answers. When, for example, an animal adopts an infant of another animal, it exhibits an evolution-defying altruistic behavior. Evolution predicts that animals will behave selfishly, seeking only to further their own reproductive success. Yet there are hundreds, perhaps thousands of examples of animals adopting babies of their own species, or even more incredibly, members of other species, sometimes across the kind or predatory boundaries. These altruistic adoptions are powerful evidence for the original “very good” design God put into his creation.

Altruism in humans is well documented. People do things that are not motivated solely by selfish benefit all the time. Something as simple as opening a door for someone or as big a commitment as adopting a child are examples of altruistic behavior in humans. Because we see it happen regularly, we are somewhat inattentive to it in humans. As conscious beings with a conscience (Rom 2:15), we expect that we and other humans will at least periodically act in an unselfish manner. While this itself is evidence against evolutionary dogma, when animals exhibit altruism, evolutionary scientists are often left scratching their heads.

Quick facts:

  • Animal adoption is not predicted by evolution.
  • Evolution has no purpose or forethought.
  • There are hundreds of cases on record of animals adopting young of other parents.
  • Adoptions occur most prominently in birds, but appear in mammals, fish, and invertebrates as well.
  • The most notable case was a lioness adopting six successive Arabian oryx calves.
  • These animal adoptions point back to God’s originally “very good” creation.

Interspecific adoption is perhaps the most obvious example of interspecific (between multiple species) cooperation. There are other examples, such as cooperative hunting between groupers and moray eels1 and cleaning behavior between cleaner shrimp and wrasses and their clients.2 However, these are mutualistic relationships, particularly that of the cleaners. Both parties get a benefit. Even intraspecific , or same species, adoption could be viewed as benefit, if not to the individual, at least to the species.

This is a stretch in light of evolutionists’ view of evolution. “Natural selection, the blind, unconscious, automatic process which Darwin discovered, and which we now know is the explanation for the existence and apparently purposeful form of all life, has no purpose in mind. It has no mind and no mind’s eye. It does not plan for the future. It has no vision, no foresight, no sight at all,”3 Richard Dawkins freely proclaims. This would seem to run counter to any form of altruism, including adoption of offspring of the same species. Yet intraspecific adoption does happen in creatures as diverse as cichlids,4,5 falcons,6 robins,7 chimpanzees,8 cheetahs,9 and even ants.10 This is directly opposite of what evolution would expect, based on the definition its own strongest proponents give it.

Intraspecific adoption is troublesome for evolutionists, since they must explain altruistic behavior when their dogma predicts a complete lack of altruism.

While intraspecific adoption is troublesome for evolution since they must explain altruistic behavior when their dogma predicts a complete lack of altruism, it is possible that an explanation could be postulated based on reproductive benefit for the species or group as a whole. An explanation of this type would have to explain why an organism cared about the future propagation of the species when Dawkins defined evolutionary mechanisms as blind,11 but it is possible. However, this explanation could not be used to explain interspecific adoption, which involves an organism adopting young of a different species, in some cases outside the baramin.12 Evolutionists recognize this. One study noted in its opening sentence: “A bird which helps raising unrelated young seems to behave maladaptively since it wastes parental effort for no genetic profit.”13 Interspecific adoption stands as powerful evidence against a blind, random process creating the animals.

Bird Adoptions

Interspecific adoption has been observed in a wide variety of animals from insects14 to mammals.15 It is most commonly encountered in birds. In some cases, this is due to nest parasitism,16 where one bird lays its eggs deliberately in the nest of another bird to effectively trick the other species into caring for their young. In others, however, it clearly has nothing to do with nest parasitism and even occasionally involves two species parenting the chicks of one species simultaneously.17

Interspecific adoption in birds occurs in all manner of bird species. Perhaps one of the most interesting examples comes from bald eagles. Bald eagles have been reported on multiple occasions to raise red-tailed hawk chicks, and in one instance were reported to be raising even a glaucous-winged gull chick.18 The researchers had no explanation for how the gull chick ended up in the nest, but, when they tagged the eaglets, they captured the gull as well. When they released the gull it “ran to the eaglet and sought cover under its wing. The eaglet willingly provided shelter for the gull chick with brooding-like behavior.”19 The gull chick was acting like a frightened younger sibling running to hid behind a bigger, tougher older sibling. It clearly was not afraid of the eaglet and felt accepted as part of the eagle family, despite the fact that eagles regularly eat gulls. Other eagle species have also been observed to perform similar adoptions.20

But eagles are not alone in this kind of adoption. A pair of nesting crows has been observed to adopt a fledgling blue jay.21 This is unusual because the species of crow in question is known to feed on fledgling blue jays. Yet this fledgling blue jay was able to simply join the nest and be fed alongside the crows’ much younger offspring.

Another remarkable example involved a king penguin caring for a skua chick and even defending it against its true parents.22 This incident is significant because it took place outside of penguin nesting territory and did not occur during nesting season. This makes the standard evolutionary explanation of misdirected parental behavior unlikely. It is made even more remarkable by the fact that skuas will regularly feed on penguin chicks and even occasionally adult penguins. There are many other examples of birds adopting other bird chicks. Species as varied as terns,23 warblers,24 petrels,25 sparrows,26 and robins27 have been observed to adopt chicks of other species. One further interesting example in birds comes from a jackdaw attempting to feed a fledgling pigeon.28 This is unique because jackdaws regularly raid nests of pigeons and feed on eggs and chicks. Further, the researcher noted that “Normally, pigeon nestlings assume a defensive position to frighten a predator. There was no such behavior in this case.”29 The researcher suggested that this jackdaw had been attempting to feed the pigeon chick previously and thus the chick was not afraid of it. The chick did not take the food, perhaps because it was well fed already, but the attempt is still remarkable and makes little evolutionary sense.

Fish and Crustacean Adoptions

While birds are the most commonly cited type of interspecific adoption, there are species of fish and crustaceans that do so as well. It is rarer in these creatures likely because many do not care for their own young at all and thus would not be adopting another species’ young. However, some species of fish and crustaceans that do care for their young have been known to adopt young of other species.

Once again, this is directly opposite what evolution would predict.

Cichlids, as noted above, will brood fry from other members of the same species.30,31 However, some species will also brood other species. This can be induced in captivity32 and is documented in the wild. Some species of cichlid practice a behavior known as “farming out,” or the transfer of young from the parents to a member of a different species that is also caring for young. One study, attempting to explain why one species of Lake Tanganiyka cichlid accepts fry from other species, some of which it normally would prey on, said, “Since a great disturbance in guarded young attracts many predators, host parents may refrain from excluding foreigners from their schools. This may explain why brood-mixing is so common in Lake Tanganiyka.”33 However, this implies that the parent cichlids could foresee this outcome, contradicting Dawkins statement that evolution has “no purpose in mind. . . . It does not plan for the future.”34 A second study observed: “It can be concluded that the decision whether to adopt or to reject a foreign brood does not depend on the brood's characteristics.”35 In other words, the mother appears to accept any fry regardless of size, morphology or behavior. Once again, this is directly opposite what evolution would predict.

While cichlid adoption is unique, the adoption performed by mysid shrimps is incredible. Mysid shrimps are tiny crustaceans found throughout the world’s oceans and are prey to many large creatures such as baleen whales. They carry their young in a small pouch on their stomach until they mature. Periodically, some female mysid shrimps will adopt larval shrimps of other species36 that happen to be floating in the water column. This occurs regardless of the size of the larva. This adoption is exceptional and confers no evolutionary benefit to the female mysid shrimp.

Mammal Adoptions

Mammals also perform these adoptions, though perhaps less often than birds and fishes. Most mammalian adoptions occur in monkeys,37 though other creatures exhibit it as well. One such case involved a troop of capuchin monkeys adopting a much smaller marmoset.38 It was observed to live with the troop of capuchins for fourteen months and was completely at home in the group, being adopted successively by two separate females and being treated the same as the capuchin infants in the troop. Marmosets are known to perform some adoptions of their own. Two separate species are known to care for infants of the other in captivity.39

Mammalian adoptions are not limited to monkeys however. Whales have been observed to do it as well. A pod of sperm whales was observed to adopt a bottle-nosed dolphin with a spinal deformity.40 They accepted the dolphin as one of their own, and it interacted with the whole pod freely and without fear. The dolphin undoubtedly benefitted from living with the sperm whales, gaining protection and companionship, but the sperm whales appeared to gain nothing from adopting the dolphin, even perhaps being slowed in their movements because of it.

Sperm whales are not the only whales to adopt. A Canadian pod of juvenile male beluga whales adopted a juvenile male narwhal that had been living alone in the St. Lawrence River for three years. The narwhal fit in very well, prompting researcher Dr. Robert Michaud to say, “It behaves like it was one of the boys.”41 While belugas and narwhals are found in the same areas, they have vastly different lifestyles and diets, making this adoption even more remarkable.

However, as remarkable as whale and monkey adoptions are, they do not come close to being the most incredible animal adoption observed in the wild. That honor goes to a female lioness from Kenya who adopted six Arabian oryx calves in succession,42 caring for them as she would her own cubs, even attempting to protect them from predators. She even seemed to recognize she could not feed them herself, permitting some of her adopted calves to feed from their real mothers before resuming parental status.43 This behavior is absolutely bizarre by evolutionary standards, particularly since big cats frequently prey on oryx and will even kill infants of their own species.44

Adoptive Implications

Something more must be at work than a simple case of hormones and mistaken identity.

Evolutionists have serious problems with interspecific animal adoptions, something many of them recognize. They have attempted to explain it using a mistaken identity idea. “Such incidents have therefore usually been attributed to reproductive errors, where individuals fail to correctly identify offspring.”45 In other words, since evolution is true, these adoptive parents must simply be mistaking these young for their own. It never dawned on them to question the dogma, not the behavior they observed. However, mistaken identity fails as a catch-all explanation based on the behavior of the female lioness with her Arabian oryx calves. She clearly knew the calves were not her cubs and demonstrated it by not trying to nurse them herself, but instead permitting their true mothers to nurse them on multiple occasions. Something more must be at work than a simple case of hormones and mistaken identity.46

From a creationist perspective, animal adoptions are powerful evidence of God’s original design in the universe.

From a creationist perspective, animal adoptions are powerful evidence of God’s original design in the universe. Genesis 1:31 tells us God made everything perfect in the beginning. That perfection would have included no death, which meant no carnivorous animals (Romans 8:20–22). The Bible confirms this in the dietary restrictions God lays down in Genesis 1:29–30. The animals would have existed in perfect harmony. Of course, this harmony was disrupted as part of the curse brought on by man’s sin (Genesis 3:17). In spite of the fallen world, however, there are still vestiges of the Edenic past in the present. In fact, when Isaiah discusses what the new earth will look like, one of the features he mentions sounds remarkably similar to the behavior of the lioness. “The wolf shall dwell with the lamb, and the leopard shall lie down with the young goat, and the calf and the lion and the fattened calf together; and a little child shall lead them,” Isaiah 11:6 tells us. Note that the lion is said to lay down with the calf. This would seem to imply an element of care for each other.


Evolutionists recognize that they have a problem with adoption. “This challenges evolutionary theory because of the apparent extremely altruistic nature of the behavior,"47 one research team wrote discussing adoption in primates. Another research team discussing penguin adoption echoed the sentiment: “This behaviour is rare and appears to conflict evolutionary theory, as kin selection is unattainable.”48 Their struggle to reconcile their observation with evolutionary dogma is illuminating.

Animal adoption defies Darwinian explanation and stands as powerful evidence against a purposeless, blind process that evolutionists propose created life.

Creationists are in a much better position when it comes to discussing animal adoptions. While this cannot be argued dogmatically, incredible adoptions like the lioness with an oryx calf and bald eagles nurturing a gull chick could point back to the original design. Isaiah tells us that the lion will lay down with the calf and that “They shall not hurt or destroy in all my holy mountain, says the LORD” (Isaiah 65:25). Perhaps these remarkable lapses of identification and predatory instinct are actually relapses to a pre-fall mindset in these creatures. A mindset where a baby is to be nurtured and cared for just like a member of their own kind would seem to fit well with the perfect world of Genesis 1. These predators caring for their prey seem to exemplify such a mindset. This would seem to make sense in light of a perfect pre-fall world and the statements from Isaiah about the future. Whether that is applicable or not, animal adoption defies Darwinian explanation and stands as powerful evidence against a purposeless, blind process that evolutionists propose created life.

Answers in Depth

2018 Volume 13


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  2. Alexandra Grutter, “Parasite Removal Rates by the Cleaner Wrasse Labroides dimidiatus,” Marine Ecology Progress Series 130 (1996): 61–70,
  3. Richard Dawkins, The Blind Watchmaker (New York: W.W. Norton & Company, Inc. 1996).
  4. Brian D. Wisenden and Miles H.A. Keenleyside, “Intraspecific Brood Adoption in Convict Cichlids: A Mutual Benefit,” Behavioral Ecology and Sociobiology 31 (1992): 263–269,
  5. Franziska C. Schaedelin, Wouter F.D. van Dongen and Rishard H. Wagner, “Non-Random Brood Mixing Suggests Adoption in a Colonial Cichlid,” Behavioral Ecology 24 no. 2 (2013): 540–546,
  6. Alexandre Anctil and Alastair Franke, “Intraspecific Adoption and Double Nest Switching in Peregrine Falcons,” Arctic Institute of North America 66 no 2 (2013): 222–225,
  7. Asa Berggren, “Intraspecific Adoption and Foster Feeding of Fledglings in the North Island Robin,” New Zealand Journal of Ecology 30 no. 2 (2006): 209–217
  8. Christophe Boesch, Camille Bole, Nadin Eckhardt, and Hedwin Boesch, “Altruism in Forest Chimpanzees: The Case of Adoption,” PLOS (2010),
  9. Sarah M. Durant, Sultana Bashir, Thomas Maddox, and M. Karen Laurenson, “Relating Long-Term Studies of Conservation Practice: the Case of the Serengeti Cheetah Project,” Conservation Biology 21 no. 3 (2007): 602–611,
  10. Kathleen P. Rudolph, and Jay P. McEntee, “Spoils of war and peace: enemy adoption and queen-right colony fusion follows costly intraspecific conflict in acacia ants.” Behavioral Ecology 27, no. 3 (2016): 793–802,
  11. Dawkins, 1996.
  12. Jason Bittel, “Why Is This Cardinal Feeding a Goldfish?” National Geographic August 3, 2017, Accessed September 20, 2018,
  13. J.M. Zuniga and T. Redondo, “Adoption of Great Spotted Cuckoo Clamator glandarius Fledglings by Magpies Pica pica,” Bird Study 39 (1992): 200–202,
  14. Hunt, James H, “Interspecific Adoption of Orphaned Nests by Polistes Paper Wasps (Hymenoptera: Vespidae),” Journal of Hymenoptera Research 18, no. 2 (2009): 136–139,
  15. R. F. Guerra, E. Takase, and C.V. Santos, “Cross Fostering Between Two Species of Marmosets (Callithrix jacchus) and (Callithrix penicillate),” Revista Brasileira de Biologia 58, no. 4 (1998),
  16. Bernard Cadiou and Y. Jacob, “Roseate Terns Sterna dougallii Successfully Rearing a Young Sandwich Tern S. sandvicensis,” Seabird 23 (2010): 139-142,
  17. Katie LaBarbera and Rae Spencer, “House Wren (Troglodytes aedon) Provisions Nestlings of Northern Cardinal (Cardinalis cardinalis),” The Wilson Journal of Ornithology 128, no. 3 (2016).
  18. Robert G. Anthony and John T. Faris, “Observations of a Live Glaucous-Winged Gull Chick in an Active Bald Eagle Nest,” The Wilson Bulletin 115 no. 4 (2003): 481–483,
  19. Ibid.
  20. Ivan Literak and Jakub Mraz, “Adoptions of Young Common Buzzards in White-Tailed Sea Eagle Nests,” The Wilson Journal of Ornithology 123 no. 1 (2011): 174–176,
  21. Kevin J. McGowan, “Nesting Crows Adopt a Fledgling Blue Jay,” Journal of Field Ornithology 62 no. 2 (1990): 171–173,
  22. W. Chris Oosthuizen and Nico de Bruyn, “King Penguins Brooding and Defending a Subantarctic Skua Chick,” Polar Biology 32 (2009): 303–305,
  23. Stephen A. Oswald, Christy N. Wails, Brittany E. Morey, and Jennifer M. Arnold, “Caspian Terns (Hydroprogne caspia) Fledge a Ring-Billed Gull (Larus delawarensis) Chick: Successful Waterbird Adoption Across Taxonomic Families,” Waterbirds 36 no. 3 (2013): 385–389,
  24. Cameron J. Fiss, Darin J. McNeil, Renae E. Poole, Karli M. Rogers, and Jeffery L. Larkin, “Prolonged Interspecific Care of Two Sibling Golden-Winged Warblers (Vermivora chrysoptera) by a Black-and-White Warbler (Mniotilta varia),” The Wilson Journal of Ornithology Vol. 128, no. 4 (2016): 921–926,
  25. Terence W. O’Dwyer, Dean Portelli, and Nicholas Carlile, “Interspecific Fostering of a Wedge-Tailed Shearwater Ardenna pacifica by White-Necked Petrels Pterodroma cervicalis on Phillip Island, Norfolk Island Group,” Marine Ornithology 46 (2018): 43–45,
  26. G.A. Lozano, and R.E. Lemon, “Adoption of Yellow Warbler Nestlings by Song Sparrows,” The Wilson Bulletin 110 no. 1 (1998): 131–133,
  27. Lowther, Peter E, “American Robin Rears Brown-headed Cowbird,” Journal of Field Ornithology 52, no. 2 (1981): 145-147,
  28. Tomasz Hetmanski, “Observations of a Jackdaw Attempting to Feed a Pigeon Fledgling,” Ukrainian Ornithological Journal 14, no. 2 (2005): 231–233,
  29. Ibid.
  30. Wiseden and Keenleyside, 1992.
  31. Schaedelin et al., 2013.
  32. Wayne S. Leibel, “Fry Recognition and Foster-Parenting in Geophagine Cichlids,” Buntbarsche Bulletin 101 (1984): 3–10,
  33. Ochi, Haruki. and Yasunobu Yanagisawa, “Interspecific brood-mixing in Tanganyikan cichlids,” Environmental Biology of Fishes 45 (1996): 141–149,
  34. Dawkins, 1996.
  35. Mrowka, Wolfgang, “Brood Adoption in a Mouthbrooding Cichlid Fish: Experiments and a Hypothesis,” Animal Behaviour 35 no. 3. (1986): 922-923,
  36. K.J. Wittmann, “Adoption, Replacement and identification of Young in Marine Mysidacea (Crustacea).” Journal of Experimental Marine Biology and Ecology 34 no. 3 (1978): 259-274,
  37. Alejandro Estrada, “A Case of Adoption of a Howler Monkey Infant (Alouatta villosa) by a Female Spider Monkey (Ateles geoffroyi),” Primates 23, no. 1 (1982): 135–137,
  38. Patricia Izar, Michele P. Verderane, Elisabetta Visalberghi, Eduardo B. Ottoni, Marino Gomes de Oliveira, Jeanne Shirley, and Dorothy Fragaszy, “Cross-Genus Adoption of a Marmoset (Callithrix jacchus) by Wild Capuchin Monkeys (Cebus libidinosus): Case Report,” American Journal of Primatology 68 (2006): 692–700,
  39. Guerra, Takase, and Santos, 1998.
  40. Linda Poon, “Deformed Dolphin Accepted into New Family,” National Geographic January 23, 2013, Accessed September 21, 2018,
  41. Emily Chung, “Beluga Whales Adopt Lost Narwhal in St. Lawrence River,” CBC, September 13, 2018. Accessed September 21, 2018,
  42. Marc Lacey, “5 Little Oryxes and the Big Bad Lioness of Kenya,” The New York Times, September 19, 2002, Accessed September 21,2018,
  43. James Still, “Lioness adopts another antelope,” The Guardian February 16, 2002, Accessed September 21, 2018,
  44. Guy A. Balme and Luke T.B. Hunter, “Why Leopards Commit Infanticide,” Animal Behaviour 86, no. 4 (2013): 791–799,
  45. Oosthuizen and de Bruyn, 2009.
  46. It should be noted that the lioness did eat one of the calves after it died naturally. However, since lions will kill their own cubs and the lioness adopted further oryx calves thereafter and never killed them, the point remains.
  47. Izar et al., 2006.
  48. Oosthuizen and de Bruyn, 2009.


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