In Belostomatidae (giant water bugs), how do the eggs obtain oxygen?

• A. Oxygen is provided by the male parent to which the eggs adhere.
• B. Oxygen diffuses through the eggshell directly from the water.
• C. The eggs have internal gills that extract oxygen from the water.
• D. The female carries air bubbles to the eggs.

Answer: (A)

In giant water bugs, the eggs are cared for by the male and receive their oxygen from the male’s own respiration. The male carries the eggs on his back, and as he breathes air at the water surface, a film of air remains around the eggs. Oxygen diffuses from that air film into the eggs, supplying the developing embryos. The eggs themselves don’t have internal gills, nor do they rely on direct diffusion from water in this case, and the female does not carry oxygen bubbles. This is a clear example of male parental care providing the necessary oxygen during incubation.