Humans and Apes joined by Humpback’s in 'Spindle Cell Brigade'

U.S. researchers examined brain cells of Humpback Whales and reported on Monday that they share intelligence equivalent to human beings, apes, and other cetaceans such as dolphins.

These cells were bragged to set humans and great apes apart from other mammals. Now even Humpback Whales have been found to have these spindle cells- specialized cells positioned in the brain occupied in processing emotions and help interact socially.

The spindle cells helps to transmit signals in the nervous system, and are characterized by a large spindle shaped soma, steadily narrowing into a sole apical dendrite (axon) in one direction, with only a single dendrite facing opposite.

Other types of neurons have large number of dendrites but having been found in only two very restricted regions in the brains, spindle cells are unique from the rest.

Scientists have discovered that these cells play an important role in a wide range of cognitive abilities, development of intelligent behavior and adaptive response to changing conditions and cognitive dissonance. The cells are largest and most abundant in humans, connected to a large part of the brain, evidencing their contributions to greater ability of hominids to focus on complicated problems.

“This might mean such whales are more intelligent than they have been given credit for, and suggests the basis for complex brains either evolved more than once, or has gone unused by most species of animals”, the researchers said.

The researchers also said that these findings will help them understand and give an explanation for the various behaviors exhibited by the whales, such as complicated communication skills, the formation of alliances, cooperation, cultural transmission and tool usage.

Not only Humpback Whales, but even Killer Whales, Fin Whales, and Sperm Whales, have spindle cells existing in the same areas of the brains as humans, i.e, anterior cingulate cortex and frontoinsular cortex.

The research was conducted by Patrick Hof and Estel Van der Gucht of the Department of Neuroscience at Mount Sinai School of Medicine, and it was also found that the Humpbacks had structures that resembled "islands" in the cerebral cortex, seen in some other mammals.

The researches suggested that the islands must have evolved in order to promote quick and efficient communication between neurons.

“It’s absolutely clear to me that these are extremely intelligent animals,” says Patrick Hof.

“We must be careful about anthropomorphic interpretation of intelligence in whales,” says Hof. “But their potential for high-level brain function, clearly demonstrated already at the behavioral level, is confirmed by the existence of neuronal types once thought unique to humans and our closest relatives,” he says.

“They communicate through huge song repertoires, recognize their own songs and make up new ones. They also form coalitions to plan hunting strategies, teach these to younger individuals, and have evolved social networks similar to those of apes and humans,” Hof says.

The spindle cells appeared in humans and apes about 15 million years ago, but the researches indicated that in cetaceans they would have evolved earlier, possibly as early as 30 million years ago.

Unlike in humans, the researchers were baffled to find spindle cells in the frontopolar cortex at the front of the brain. Hof says “I do not yet know the significance of spindles found in areas other than those that contain the cells in humans and great apes”.

The functioning of the spindle cells is still under investigation but Hof strongly believes that the cells help in carrying messages to and fro from parts of the cortex.

The Humpback Whales are migratory species found in almost all oceans, spending its summers in cooler, high-latitude waters, but mating and calving in tropical and sub-tropical waters. Annually, it migrates 25,000 km, making it the most traveled mammalian specie. However, the Whales in the Arabian Sea do not migrate and remain in the tropical waters year round.

The species is not found in the eastern Mediterranean, the Baltic Sea or the Arctic Ocean.