Adaptation
Most adaptations of Stenotrema hirsutum and other terrestrial land snails have had to do with the ability to breathe air and limiting water loss (Nordsiek, 2010).
The terrestrial land snail adapted by heavily reducing the size and use of the gill because it is only able to acquire oxygen from water (Nordsiek, 2010). Oxygen in the air can now be acquired through the tissues of the pallial cavity wall (Nordsiek, 2010).
While the mantle of the snail serves as protection against
predators, it has also adapted to prevent evaporation and water loss
(Nordsiek,
2010). The flow of air into the mantle cavity now must go
through the pneumostome, or respiratory hole. The snail can
control the amount of air flow and water loss through the
respiratory hole using the ring muscle
(Nordsiek,
2010).
A snail's slime also protects against water loss. The slime actually attracts water instead of releasing it (Nordsiek, 2010).
Glands in the muscular foot secrete a mucus that allows the snails to glide over rough surfaces (Martin, 2000). In order to avoid water loss during locomotion, snails have adapted a new kind of movement called "jumping". Snails are only able to move by crawling on certain parts of their foot sole, thus leaving a discontinuous trail of water making it look like they "jumped" (Nordsiek, 2010). Image of Stenotrema hirsutum by Kevin Ripka
As well as physical adaptations, the snails have also made adaptations to their behaviors. Now when the weather outside is too dry, the snails look for a suitable place to hide out, like under a log or underground.
Terrestrial snails have a sense of smell, taste, touch, and highly developed eye sight (Hickman et al.. 2007).
As well as these senses, the snails foot is able to adapt and move across any surface, even upside down! Knowing its own body positioning is an example of a static sense (Nordsiek, 2010).
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