Misconceptions Of Water Varying Habits

When the tide is high and waves crash about, air is mixed with the water, thus increasing oxygen content. This is due to the fact that when waves crash about, the water will be more exposed to the air and cause an increase in the amount of oxygen present in the water. When the tide is low and periwinkles are exposed, there is no shortage of oxygen for the periwinkle snails either because the surrounding air is composed of around 21% oxygen, which is enough oxygen for a periwinkle snail. To survive in conditions that change often, periwinkles keep their mantle cavity filled with water. This prevents the gills from collapsing as the gills will be supported and moist, allowing them function effectively. When the oxygen from the water is used …show more content…
During the colder months, snails may move to upper intertidal zones to prevent being washed away by large, violent waves as well increase exposure to the sun to increase body temperature. In comparison, during summer months, they tend to retreat to lower intertidal zones when the waves are more gentle and they can acquire some relief from the scorching sun. c) Behavioural adaptations: A behavioural adaptation of these periwinkles is that they actively seek out crevices in rocks to lodge themselves in, to reduce the drying effect of sun and wind during exposed periods. Another behaviour adaptation that also helps with the exposure, is that periwinkles can orient their shell towards the sun to reduce the surface area exposed to the light. They also tend to cluster together, sometimes in their thousands, which also helps prevent water loss.

d) Shell composition : They have a thick shell to reduce water loss, and radiation effects. This is because due to the lower density of air compared to water, abiotic factors such as light, and so heat and radiation etc, is much more potent as the snails are