Scorpion in general belong to a very old order of arthropods, Arachnida. The very first scorpion was believed to have appeared some 425 million years ago during the Silurian era, where they lived almost entirely in water. Scorpions had undergone few changes for the past millions of years, and the most impressive parts of the scorpion are the padipalps (the "claws") and the telson (the "sting"). The telson manufactures and contains the venom, which is often used to overcome large prey like small vertebrates and large invertebrates, for example mice and large beetles.

The family Scorpionidae

The Black Scorpion Heterometrus longimanus is a resident of tropical asia, and is abundant in SE Asia, particularly Singapore, Malaysia and Thailand. The scorpions used in this study were found in Malaysia. H.longimanus belongs to the family Scorpionidae, which is an Old World group that was believed to have originated from Gondwanaland In the family Scorpionidae, where the venom of these scorpions are normally not considered lethal, H.longimanus is, therefore, not considered a medically- important scorpion species. In terms of toxicity, the LD50 (lethal dose) and molecular structure of H.longimanus has yet been concluded. Due to the low number of deaths caused by this specie, little has been researched regarding the specie. (A sub-adult Heterometrus longimanus scorpion)

Milking

In our experiments, the Heterometrus longimanus were "milked" (a word to describe the process of extracting crude venom) at the premises of Department of Anatomy, National University of Singapore. We used the new electric-shock method, where the telson was given a series of very regular currents to shock the scorpion into ejecting the venom. There are several advantages to this method of milking as compared to earlier methods, where the scorpions were made to sting an object. First, there is little wastage of venom, as nearly 100% of the venom ejected will be collected in the collecting vials. There is also less contamination of the venom as this method can easily be done in a sterile environment. In order to milk the scorpions successfully, we made use of Professor P.Gopalakrishnakone's Holding Device, which he had designed himself. The scorpion in trapped in the Holding Device, with its entire tail jutting out from one end, while the scorpion's body is inside the device and is unable use its padipalps to pinch or cause harm.

Ecology/captivity

We will touch a little on the ecology of scorpions and scorpions in captvity. Scorpions are generally found in every continent in the world except for the poles, as the temperatures there are much too cold. Otherwise, scorpions reside in almost any microhabitat, ranging from tree tops to deserts to mountain crevices to tubdras to rainforests to grasslands to houses. H.longimanus is one such scorpion that lives in forests or sheltered scrublands. It also exhibits social behavior, which is rare among scorpions, as they are sometimes found clustered together in congregations of 8-15 individuals that range very much in size. Even pregnant females have been found to live peacefully with other members of the habitat. In captivity, there are different conditions in which scorpions are kept. First, there are laboratory conditions, where they are just made to kept alive for experimental purposes. This method of captivity has been proven to be ineffective. Under simulated conditions, the habitats of the scorpions are reproduced so as to acclimatize them. This has been very successful, and the populations kept in these conditions have even been known to increase, albeit at a slow rate.