Ocean Zones

Sunlight zone (Epipelagic), Twilight zone (Mesopelagic), Midnight zone (Bathypelagic), Abyssal zone (Abyssopelagic), Hadal zone (Trenches).

Light Penetration

• Sunlight is absorbed rapidly as it travels through water.
• Red, orange, and yellow wavelengths are absorbed quickly, leaving blue visible.

Midnight Zone Depth

Extends from 1,000 meters to 4,000 meters reaching the ocean floor in many areas.

Habitat Significance

The midnight zone is the largest habitat on Earth, accounting for 70% of all seawater.

Temperature

Steady temperature of around 4° Celsius (39° Fahrenheit).

Pressure

Ranges from 100 to 400 atmospheres, increasing with depth.

Adaptations of Organisms

• Well-developed visual systems, Bioluminescence for luring prey and attracting mates.
• Enhanced auditory systems to detect nearby movements.
• Ability to withstand extreme cold and hydrostatic pressure.

PRACTICE QUESTION

Q.The term "Bathydevius Caudactylus" recently in the news in the context of which of the following?

(a) A newly discovered species of mollusk

(b) A flowering plant found in the Eastern Ghats

(c) A newly discovered virus

(d) A new variant of the coronavirus

Answer: a

Explanation:

A new species of mollusk, Bathydevius, has been discovered in the ocean's midnight zone. Unlike typical sea slugs, this bioluminescent species has a paddle-like tail, a large gelatinous hood, and swims in the deep ocean. It moves by flexing its body or drifting in currents and is hermaphroditic, possessing both male and female reproductive organs.