How do snail Reproduce?*from Chor Kia Kwee

Two types of snail

a) Hermaphrodites
A snail which has both male and female reproductive organs.
For example, land snails and most marine snails.

b) Dioecious
A snail has separated sexes
For example, Apple Snails,freshwater and marine species.

Anatomy of a snail

Fertilisation
a)External fertilisation

Dioecious

Fertilisation takes place externally in the water.
Eg. Archaic prosobranch snails (Patellogastropoda).
Sperm and egg cells are released into the water and fertilisation occurs by chance.

b)Internal fertilisation
Hermaphrodites

Land snail
During courtship, each snail manoeuvres to get its genital pore in the best position, close to the other snail's body. Then, when the body of one snail touches the other snail's genital pore, it triggers the firing of the “love dart”.

S-dart sac, D-love dart,P-penis

Love darts are used as part of the sequence of events during courtship before actual mating takes place.

During mating, both penises are entwined and inserted into the mate's vagina.

                                     Can you see the dart of the snail on the left?

Each snail would stimulate the other snail into exchanging small packets of sperm..

After mating is complete sperm packet, called spermatophore, is produced in either snail's body and afterwards filled with sperm cells.
The snails will then produce eggs internally, which are fertilised by the sperm that has been exchanged.
Up to about a month after mating the snail lays about a hundred small white eggs in a nest


The advantage of an internal fertilisation

The eggs are provided with additional nutritive cells (yolk) as well as with protective coats inside the snail, such as egg shells (terrestrial snails) or egg capsules (many sea snails, such as the whelk).

A snail can carry up to 100 eggs at a time.

It lays eggs and buries them into a cool place.
 For land snails, they will be buried underneath the dirt in order to be cared for. With marine snails, the eggs will be placed next to a solid area, such as a rock.
This will allow the eggs to stay in the same place and develop without being harmed.


A snail egg two to four weeks in order to develop.
They hatch by either eating their own egg or eating other eggs in order to get the extra nutrients. It will take around three months for the snails to completely form. While this takes place, they will stay in a nest that has been built for them, with the transformations being seen through a change in color, from a clear colour into blue then into the adult form that is representative of the species.

Question:
How do snails find a mate?

The method used is slime trail following.

Reflection
           How many times have we passed by a snail without noticing its existence?In life, we are too oblivious to our surroundings and the beauty of nature that seldom does one ponder how this small and soft animal make its living.

        
           Through this research, I was awestruck by the incredible organ make-ups of the snails. I become more appreciative that every organism is unique and gain insights that every organ serves its own purpose for the survival of an organism.

         
            Besides that, it deeply provides me food for thought.A snail, no matter how slow, would still complete its journey in order to accomplish its objective which is to find its mate. I was captured and intrigued by the determination of the snail. It works single-mindedly and has invincible belief in its own ability towards its goal.
  
    
          "Sometimes in life,we're moving slow...
                 There’s nothing wrong moving on a snail’s pace...
                        Slow and steady running its own race...
                            And it knows where the finishing line is...__"
                                                                             ~Kia Kwee