GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - IH4E_676FYJE15G0K

When studying shrimp feeding from hydro-thermal vents at the bottom of the ocean, biologists were surprised that the shrimps' reproductive cycles followed seasonal patterns. Far beyond the reach of sunlight, and with food abundant around the vents all year round, why should such animals reproduce seasonally? The answer might involve their offspring, which in their larval form drift in the currents to colonize new vents. The larvae must feed during their trip, and their springtime release coincides with a peak in algae raining down from surface waters. So far, researchers have found no evidence of seasonal breeding among vent-dwelling species that provide their offspring with yolk to sustain them or among vent-dwelling species found in areas of the ocean with not seasonal algae blooms.