Crows count their own calls, elephants use name-like calls, dolphins pass the mirror test. What studies show about animal minds and what they do not.
Scientists studying animal behavior keep finding abilities that were once thought to be uniquely human. Crows can produce a set number of calls on cue, elephants appear to call each other by name, and dolphins recognize themselves in mirrors. None of this makes animals "as smart as humans", but it does change how researchers think about where complex cognition comes from.
In April 2024, a group of scientists and philosophers issued the New York Declaration on Animal Consciousness. It states that there is strong scientific support for conscious experience in mammals and birds, and at least a realistic possibility of it in all vertebrates and many invertebrates. The declaration has since gathered more than 600 signatures.
The research also points to a pattern: similar abilities appear in animals with very different brains, such as birds and mammals, which suggests that complex cognition evolved more than once.
Crows Show Signs of Conscious Perception and Counting
Much of the strongest work on bird cognition comes from Andreas Nieder's lab at the University of Tübingen in Germany, which studies carrion crows.
In a 2020 study in Science, the team recorded single neurons in the crow pallium, the part of the bird forebrain that does the work of the mammalian cortex, while crows reported whether they had seen a faint visual stimulus. The neural activity came in two stages:
- An early stage that mainly tracked how strong the stimulus physically was
- A later stage that predicted what the crow reported seeing, whether or not a stimulus was actually there
The authors argued that this later activity is an empirical marker of sensory consciousness in birds, and that conscious perception does not require a layered cerebral cortex like ours.
In a 2024 Science study, the same lab trained crows to produce one to four calls in response to cues linked to those numbers. The sound of the first call predicted how many calls would follow, which suggests the birds planned the sequence before starting. The researchers could even read counting errors from the calls.
Elephants Use Name-Like Calls and Respond to Their Dead
A June 2024 study in Nature Ecology & Evolution used machine learning to analyze rumbles from wild African elephants in Kenya. The researchers could predict which elephant a call was addressed to from its acoustic structure, and elephants reacted more strongly to playbacks of calls originally addressed to them. Unlike dolphins and parrots, which imitate the calls of the animal they address, elephants appear to use labels that are not imitations, which is closer to how human names work.
Other research documents elephant social and emotional behavior:
- Consolation: A 2014 study at a camp in Thailand found Asian elephants touched and vocalized to distressed companions more after a distress event than in control periods, which the authors classed with consolation in apes.
- Responses to the dead: A 2020 review of field reports, plus observations in Kenya's Samburu National Reserve, found that elephants approach, touch and investigate carcasses, and sometimes visit and revisit them.
- Broad interest: Elephants showed interest in dead elephants regardless of how close their relationship had been.
The review's authors describe these responses as apparently emotional but say they need more study. Whether elephants grieve in the human sense is still an open question.
Dolphins Pass the Mirror Test and Use Vocal Labels
In a 2001 study in PNAS, two captive bottlenose dolphins were marked on their bodies and given access to reflective surfaces. Both used the mirror to inspect the marked areas. Before that, only humans and great apes had shown convincing evidence of mirror self-recognition.
Dolphin communication research has found:
- Signature whistles: Each bottlenose dolphin develops its own identity whistle
- Vocal labels: Wild dolphins call back when they hear a copy of their own signature whistle, but not other whistles, which suggests copied whistles are used to address specific individuals (2013 PNAS study)
- Tool use as culture: In Shark Bay, Australia, some dolphins carry marine sponges while foraging. A 2005 genetic study found the behavior passes mostly from mothers to daughters within one family line.
Similar Abilities in Very Different Animals
Chimpanzees at Gombe Stream National Park in Tanzania choose their termite-fishing tools with care. A 2025 study in iScience measured how much force it took to bend plant materials. Plant species the chimpanzees never used were 175% more rigid than their preferred materials, and even within the same species, plants that showed signs of use produced more flexible tools. Flexible probes follow winding termite tunnels more easily.
Southern sea otters use rocks and other hard objects to crack open prey. A 2024 study in Science that tracked 196 radio-tagged otters found that tool users, particularly females, could access larger or harder-shelled prey and suffered less tooth damage.
The New York Declaration also argues that "when there is a realistic possibility of conscious experience in an animal, it is irresponsible to ignore that possibility in decisions affecting that animal."
Together, these findings suggest that advanced cognition did not arise along a single evolutionary branch leading to humans. Birds, elephants, dolphins and apes have each developed sophisticated abilities in their own ways. For more on how social understanding works in the human brain, see our article on mirror neurons and empathy.
Sources
- A neural correlate of sensory consciousness in a corvid bird, Nieder, Wagener and Rinnert, Science, 2020
- Crows "count" the number of self-generated vocalizations, Liao, Brecht, Veit and Nieder, Science, 2024
- African elephants address one another with individually specific name-like calls, Pardo et al., Nature Ecology & Evolution, 2024
- Asian elephants (Elephas maximus) reassure others in distress, Plotnik and de Waal, PeerJ, 2014
- Elephant behavior toward the dead: A review and insights from field observations, Goldenberg and Wittemyer, Primates, 2020
- Mirror self-recognition in the bottlenose dolphin: A case of cognitive convergence, Reiss and Marino, PNAS, 2001
- Bottlenose dolphins can use learned vocal labels to address each other, King and Janik, PNAS, 2013
- Cultural transmission of tool use in bottlenose dolphins, Krützen et al., PNAS, 2005
- Engineering skills in the manufacture of tools by wild chimpanzees, Pascual-Garrido et al., iScience, 2025 (University of Oxford summary)
- Tool use increases mechanical foraging success and tooth health in southern sea otters, Law et al., Science, 2024
- The New York Declaration on Animal Consciousness, New York University, April 19, 2024
