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here is an essay i wrote for my first paper in writing class. enjoy!
Man has, since his inception in the book of Genesis, been lord of all that is around him. Clearly, mankind has been a powerful influence on nature. Mankind has domesticated the wild beasts, wiped out species, and even brought them back from the very brink of destruction. But even more intriguing as well as inspiring than our power over nature; are the ways that nature has adapted to us. In Brazil, scientists have made a fascinating discovery that illustrates this point.
One of the most notorious--as well as dangerous--creatures in Brazil is the Brazilian devil scorpion, Tityus serrulatus (Lutz & Mello, 1922); a member of the Tityus stigmuris complex of scorpions (Thorell, 1877). This scorpion is quickly becoming a major health threat in Brazil due to its potent venom and prolific takeover of Brazil (Lourenco & Cloudsley-Thompson, 1996). But the most fascinating aspect of this creature is not the life it takes; but rather the life it gives. Originally it was believed that this species was entirely parthenogenic; which means that rather than having males and females, the entire species is female. Instead of sexually reproducing, the females are born with eggs that divide without being fertilized; meaning that these scorpions are essentially cloning themselves.
A pair of scientists (Wilson R. Lourenco & John L. Cloudsley-Thompson) working to understand the rapid dispersal of T. serrulatus throughout Brazil, via populational studies, stumbled upon something that questioned the natural history of these scorpions. In a remote area of the rainforests, Lourenco and Cloudsley-Thompson discovered a population of T. serrulatus containing both males and females. This raises several questions. Why is this population sexual; is this mutation, or evolution?
After the discovery of the sexual population of the Brazilian devil scorpion, several more were uncovered. As scientists mapped these populations, a strange pattern—far too strange to be coincidence—arose. The reason that T. serrulatus has adapted to mankind’s expanding presence in Brazil has always been attributed to the scorpions’ parthenogenic properties. But after mapping out the various populations of T. serrulatus in Brazil (with special regard to their methods of reproduction), it has become clear that this parthenogenesis is actually an adaptation to our presence.
All sexual populations of devil scorpions have been discovered in remote and isolated areas; whereas the parthenogenic populations are only found in urbanized areas (Lourenco & Cuellar, 1995; Lourenco & Cloudsley-Thompson, 1996; Lourenco et al. 1996). What this means is that in some way or another, the presence of man and the subsequent urbanization of Brazil has spurred the devil scorpions to stop breeding through conventional methods, and instead become parthenogenic.
Recently, Lourenco has made observations that have yet to be published, about another scorpion from this complex: Tityus stigmuris. Lourenco noted that this scorpion, once prevalent throughout all of Brazil, is now mainly isolated to the northern, less inhabited half of the country; while the southern, costal regions of Brazil are densely populated with its parthenogenic cousin, T. serrulatus. Tityus stigmuris has been documented as having both sexual and parthenogenic populations. As the species begins to thin out in southern Brazil, the remaining populations are found to be parthenogenic; whereas if one were to document the breeding habits of this species, they would find that sexual reproduction becomes more prevalent in the northern region of this species’ population. What this means is that in areas inhabited by man, the breeding trend of scorpions in said areas is becoming parthenogenic. With time, perhaps these species will abandon sexual populations altogether.
Obviously, the question on scientists’ lips is: why? What is it about our presence that has influenced these animals to change their life history so drastically? Perhaps as scientists like Lourenco crack away at this mystery we will be given insight into things we never even began to contemplate before. If our mere presence has made such a drastic change in an animal that has changed so little over millions of years; what else are we capable of? In the midst of these curiosities and questions, any person cannot deny that our race has a powerful influence on this planet and its inhabitants. One need only look to the devil scorpions of Brazil for assurance.
Man has, since his inception in the book of Genesis, been lord of all that is around him. Clearly, mankind has been a powerful influence on nature. Mankind has domesticated the wild beasts, wiped out species, and even brought them back from the very brink of destruction. But even more intriguing as well as inspiring than our power over nature; are the ways that nature has adapted to us. In Brazil, scientists have made a fascinating discovery that illustrates this point.
One of the most notorious--as well as dangerous--creatures in Brazil is the Brazilian devil scorpion, Tityus serrulatus (Lutz & Mello, 1922); a member of the Tityus stigmuris complex of scorpions (Thorell, 1877). This scorpion is quickly becoming a major health threat in Brazil due to its potent venom and prolific takeover of Brazil (Lourenco & Cloudsley-Thompson, 1996). But the most fascinating aspect of this creature is not the life it takes; but rather the life it gives. Originally it was believed that this species was entirely parthenogenic; which means that rather than having males and females, the entire species is female. Instead of sexually reproducing, the females are born with eggs that divide without being fertilized; meaning that these scorpions are essentially cloning themselves.
A pair of scientists (Wilson R. Lourenco & John L. Cloudsley-Thompson) working to understand the rapid dispersal of T. serrulatus throughout Brazil, via populational studies, stumbled upon something that questioned the natural history of these scorpions. In a remote area of the rainforests, Lourenco and Cloudsley-Thompson discovered a population of T. serrulatus containing both males and females. This raises several questions. Why is this population sexual; is this mutation, or evolution?
After the discovery of the sexual population of the Brazilian devil scorpion, several more were uncovered. As scientists mapped these populations, a strange pattern—far too strange to be coincidence—arose. The reason that T. serrulatus has adapted to mankind’s expanding presence in Brazil has always been attributed to the scorpions’ parthenogenic properties. But after mapping out the various populations of T. serrulatus in Brazil (with special regard to their methods of reproduction), it has become clear that this parthenogenesis is actually an adaptation to our presence.
All sexual populations of devil scorpions have been discovered in remote and isolated areas; whereas the parthenogenic populations are only found in urbanized areas (Lourenco & Cuellar, 1995; Lourenco & Cloudsley-Thompson, 1996; Lourenco et al. 1996). What this means is that in some way or another, the presence of man and the subsequent urbanization of Brazil has spurred the devil scorpions to stop breeding through conventional methods, and instead become parthenogenic.
Recently, Lourenco has made observations that have yet to be published, about another scorpion from this complex: Tityus stigmuris. Lourenco noted that this scorpion, once prevalent throughout all of Brazil, is now mainly isolated to the northern, less inhabited half of the country; while the southern, costal regions of Brazil are densely populated with its parthenogenic cousin, T. serrulatus. Tityus stigmuris has been documented as having both sexual and parthenogenic populations. As the species begins to thin out in southern Brazil, the remaining populations are found to be parthenogenic; whereas if one were to document the breeding habits of this species, they would find that sexual reproduction becomes more prevalent in the northern region of this species’ population. What this means is that in areas inhabited by man, the breeding trend of scorpions in said areas is becoming parthenogenic. With time, perhaps these species will abandon sexual populations altogether.
Obviously, the question on scientists’ lips is: why? What is it about our presence that has influenced these animals to change their life history so drastically? Perhaps as scientists like Lourenco crack away at this mystery we will be given insight into things we never even began to contemplate before. If our mere presence has made such a drastic change in an animal that has changed so little over millions of years; what else are we capable of? In the midst of these curiosities and questions, any person cannot deny that our race has a powerful influence on this planet and its inhabitants. One need only look to the devil scorpions of Brazil for assurance.
