Hey, this is not reptilian but none the less it explains few things. LOL This extract is from an article I have written for the Asian Geographic some years ago. The introduction and the second part was about the life of dung beetles - juicy stuff! They didn't publish it .....
Snails and slugs belong to the class Gastropoda, which first appeared in marine environments in the early Cambrian period. Later, it is believed, many swapped gills for lungs and evolved into terrestrial or freshwater gastropods. Whilst in the ocean, these creatures had no problems with their daily lives and bodily functions but that situation changed drastically once they stepped onto dry land. There was a major problem with their anatomy. The primitive snails had planospiral shells, which were bilaterally symmetrical and looked like a house that is coiled flat on the ground. One can hardly imagine how the poor critters travelled around with this cumbersome coil, not to mention the difficulties they must have had in getting through tight spaces. But awkward mobility was the least of their problems.
These unfortunate creatures were cursed because their anuses were positioned directly above their heads! Being slow on the foot was always a snail’s handicap but the severe helplessness in personal hygiene must have caused deep embarrassment. The poor things kept fouling their faces for millions of years until they were released from their misery by a much kinder evolutionary adaptation - body torsion and an asymmetrical shell. The shell as well as the visceral mass turned, and this not only changed the shape of the shell into that we know in living snails, but it also served to shift the anus to where it supposed to be – at the posterior.
If you wonder why modern snails move around ever so slowly, they are probably just taking their time to enjoy their much-improved lifestyle – at last! Those of you who don’t believe in evolution and think that God created everything – think again, what a cruel joke that would have been!
Snails and slugs belong to the class Gastropoda, which first appeared in marine environments in the early Cambrian period. Later, it is believed, many swapped gills for lungs and evolved into terrestrial or freshwater gastropods. Whilst in the ocean, these creatures had no problems with their daily lives and bodily functions but that situation changed drastically once they stepped onto dry land. There was a major problem with their anatomy. The primitive snails had planospiral shells, which were bilaterally symmetrical and looked like a house that is coiled flat on the ground. One can hardly imagine how the poor critters travelled around with this cumbersome coil, not to mention the difficulties they must have had in getting through tight spaces. But awkward mobility was the least of their problems.
These unfortunate creatures were cursed because their anuses were positioned directly above their heads! Being slow on the foot was always a snail’s handicap but the severe helplessness in personal hygiene must have caused deep embarrassment. The poor things kept fouling their faces for millions of years until they were released from their misery by a much kinder evolutionary adaptation - body torsion and an asymmetrical shell. The shell as well as the visceral mass turned, and this not only changed the shape of the shell into that we know in living snails, but it also served to shift the anus to where it supposed to be – at the posterior.
If you wonder why modern snails move around ever so slowly, they are probably just taking their time to enjoy their much-improved lifestyle – at last! Those of you who don’t believe in evolution and think that God created everything – think again, what a cruel joke that would have been!