Big Blue Octopus

The Octopus cyanea, commonly known as the big blue octopus or day octopus, is a member of the Octopodidae family. It can be found in both the Pacific and 🌊 Indian Oceans, ranging from Hawaii (🇺🇸 United States) to the eastern coast of Africa. The mantle length of O. cyanea can reach up to 16 cm, with arms extending to at least 80 cm. This species was first described by the British zoologist John Edward Gray in 1849 and the type specimen is housed at the Natural History Museum in London.

In its natural habitat of coral reefs, Octopus cyanea exhibits exceptional camouflage skills and is capable of rapidly changing its color, patterns, and texture to blend with its surroundings. Researchers have observed this octopus change its appearance up to 1000 times in just seven hours. When stationary near prey, such as a crab, it may display a "passing clouds" behavior, appearing as if a dark shadow is passing over its surface to potentially deceive the crab.

The distribution of Octopus cyanea spans the Indo-Pacific region, including the 🌊 Red Sea, East African coast, 🇲🇬 Madagascar, southeastern Asia, Oceania, and Hawaii.

Unlike most octopus species that are nocturnal, Octopus cyanea is diurnal, with its peak activity occurring at dawn and dusk. It establishes a den, which serves as its refuge when not foraging. This den can be located in a rock crevice, under an overhang, among coral heads, or even a hole it creates in rubble or sand. Octopus cyanea is a predator that preys on fish, crabs, shrimp, and molluscs. Smaller prey is typically consumed on the spot, while larger items are carried back to the den for consumption. Crabs are killed through a bite and injected with toxic saliva before being consumed, while molluscs have their shells drilled and the animal inside is predigested to facilitate extraction. The discarded shells and carapaces form a midden outside the den. Octopus cyanea occasionally engages in cooperative hunting with the roving coral grouper. The lifespan of Octopus cyanea is approximately 12-15 months, during which it grows exponentially.

The Big Blue Octopus (Octopus cyanea) has several interesting biological features related to its heart and brain:

• Heart: Octopus cyanea, like other octopus species, has three hearts. Two of these hearts are branchial hearts, which pump blood through the gills, where oxygen is absorbed. The third heart, known as the systemic heart, pumps oxygenated blood to the rest of the body. This unique circulatory system allows for efficient oxygenation of the octopus's blood and tissues.

• Blood: Octopuses, including Octopus cyanea, have copper-based blood, unlike humans and most other vertebrates, which have iron-based blood. The copper-based molecule, hemocyanin, gives their blood a bluish color and helps transport oxygen throughout their bodies.

• Brain: Octopus cyanea possesses a highly developed and complex nervous system. The majority of the octopus's neurons are located in its arms, which allow them to perform intricate tasks and manipulate objects with remarkable dexterity. Additionally, their brains exhibit considerable intelligence and problem-solving capabilities, making octopuses some of the most intelligent invertebrates.

• Neurological Adaptations: The octopus brain is distributed throughout its body, with a large portion of neurons located in its arms. This decentralized nervous system enables each arm to exhibit some level of independent decision-making and motor control. This decentralized nature contributes to their exceptional ability to multitask, solve problems, and coordinate complex movements.

• Learning and Memory: Octopus cyanea, along with other octopus species, has demonstrated impressive learning abilities and memory retention. They can learn from experiences, remember solutions to problems, and adapt their behavior accordingly, indicating a sophisticated level of cognition.

Understanding the anatomy and physiology of the Big Blue Octopus's heart and brain provides valuable insights into its remarkable abilities, behavior, and adaptations to its environment. The complex nature of their nervous system and circulatory system contributes to their survival and success in the marine environment.