Tremendous photo, Aaron!
What is that white thing they are eating? Wy does the slug nearest camera have a hole in its back?
What is that white thing they are eating?oh, lol. Can I answer its penis?
( from
http://en.wikipedia.org/wiki/Slug )
Slugs are hermaphrodites, having both female and male reproductive organs.
Once a slug has located a mate, they encircle each other and sperm is exchanged through their protruded genitalia. [ The white thing ] A few days later the slugs lay around 30 eggs in a hole in the ground, or beneath the cover of an object such as a fallen log.
Apophallation is a commonly seen practice among many slugs. In apophallating species, the penis curls like a corkscrew and during mating often becomes entangled in the mate's genitalia. Apophallation allows the slugs to separate themselves by one or both of the slugs chewing off the other's penis. Once its penis has been removed, the slug is still able to mate using only the female parts of its reproductive system.
http://www.youtube.com/watch?v=FhVi4Z6CjZk (I'll leave this as a link so as to not spoil the photographic nature of this thread.
Why does the slug nearest camera have a hole in its back?( from
http://en.wikipedia.org/wiki/Slug and
http://en.wikipedia.org/wiki/Pneumostome )
On one side (almost always the right hand side) of the mantle is a respiratory opening, which is easy to see when open, but difficult to see when closed. This opening is known as the pneumostome.
The pneumostome (or breathing pore) is a feature (the respiratory opening) of the external body anatomy of an air-breathing land slug or land snail. It is a part of the respiratory system of gastropods.
It is an opening in the right side of the mantle of a Pulmonata or subcladed Stylommatophora or snail. Air enters through the pneumostome into the animal's single lung, the air-filled mantle cavity.
The pneumostome is often much easier to see in slugs than in snails, because of the absence of a shell. The pneumostome is usually very clearly visible on the right side of the animal when the pneumostome is wide open. However, the position of the pneumostome is often not at all easy to discern when the pneumostome is closed.
The pneumostome opens and closes in a cyclical manner. The frequency of pneumostome closing and opening is typically less than 0.5 closures per minute in fully hydrated slugs and snails. The rate of closures per minute increases the more dehydrated the slug is.
I didn't know until I googled after I took the photo either, I hope they didn't think I was being a voyeur!
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