Marine Insects and the Sea-Skater Halobates (Hemiptera: Gerridae)

Although insects originated in swampy areas some 300 millions years ago, they then moved toward a terrestrial existence, evolving various physiological adaptations which allowed them to become independent of water or damp places, and to achieve dispersal though the air.

Some of the most important adaptations of many insects living on land include the following:

• Hardened, impermeable cuticle often impregnated with lipids to cut down on water loss.

• Tracheal breathing system for efficient distribution of oxygen by diffusion.

• Wings for long-range aerial dispersal.

• Complete metamorphosis, which may allow adults and young to exploit completely different habitats.

Surviving the Marine Environment

In order to return to the sea they have had to solve a number of ecological, physiological as well as physical problems. Some of these problems, e.g., osmotic regulation, they have succeeded in solving, while others, e.g., underwater respiration, are perhaps insurmountable, hence the rarity of...