Figure 4. Thalassia hemprichii seedlings anchor to a bed of coral sand but not silicate sand.

Seeds were allowed to germinate on beds of silicate or coral sand in the same aquarium. Seedlings anchored themselves using root and root hairs to grip coral sand (A, right and B) but not silicate sand (A, left and B; Chi-square test, p<0.01). Seedlings not anchored were floating in the water column when the vegetative tissues became dominant (A, left).