The animal kingdom, from the most simple organisms, is endowed with a fascinating array of sensory capabilities. The need to sense changes in the surroundings is essential for the survival of living organisms and help them to adapt or escape. Communication using sensory cells is also used between different organisms for social behavior and self-defense.
The Octopus has various adaptations that make it an unusual yet versatile survivor of adverse conditions. They use their arms to feel the floor of the ocean and use what is termed as a “taste by touch” mechanism to detect prey and food. Although research has been done over the decades to understand the nervous system of the Octopus, the exact molecular mechanism by which it can detect chemicals is beginning to come to light.
A research study published in the journal Cell describes how these animals of the sea can taste and feel the chemicals around them. The research team from Harvard showed that the suction cups on the arms of the octopus have a superficial layer of cells that can detect substances that are not dissolved in water. These sensors, called Chemotactile receptors, helped the octopus to learn about its’ surroundings and detect what might be edible (such as molecules on the surface of a crab) through both the texture and the flavor. The sensors sent this information back to their nervous systems. Each arm is independent and has its’ own nervous system.
Chemotactile as the word implies, is literally the ability to feel chemicals. Generally when we think of the senses, we recall vision, smell, taste, hearing and touch. Additionally there are “sensory” receptors in our body organs that are able to pick up different kinds of cues, such as chemicals or temperature or pain.
Understanding the molecular mechanisms of various sensors in nature can help us to unravel the science behind how different parts of our body communicate with each other and also adjust to the environment. Chemotactile receptors are highly specialized sensors and this research opens up many new doors for developing nano machines that can behave as sensors for detecting chemicals in the environment, ocean floor or even in space exploration.
Bibliography
Harvard University. "Touch and taste? It's all in the tentacles: Researchers uncover how the sensors in octopus suction cups work." ScienceDaily. ScienceDaily, 29 October 2020. <www.sciencedaily.com/releases/2020/10/201029142025.htm>.
Siliezar, Juan. “Octopus' Suction Cups Hold Its Taste and Touch Sensors.” Harvard Gazette, Harvard Gazette, 29 Oct. 2020, news.harvard.edu/gazette/story/2020/10/octopus-suction-cups-hold-its-taste-and-touch-sensors/.
van Giesen et al. Molecular basis of chemotactile sensation in octopus. Cell, 2020 DOI: 10.1016/j.cell.2020.09.008
