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〃And the second reason？〃
〃All the animals in Jurassic Park are female；〃 Wu said； with a pleased smile。
Malcolm said； 〃I should like some clarification about this。 Because it seems to me that irradiation is fraught with uncertainty。 The radiation dose may be wrong； or aimed at the wrong anatomical area of the animal…〃
〃All true；〃 Wu said。 〃But we're quite confident we have destroyed gonadal tissue。〃
〃And as for them all being female；〃 Malcolm said； 〃is that checked？ Does anyone go out and； ah； lift up the dinosaurs' skirts to have a look？ I mean； how does one determine the sex of a dinosaur； anyway？〃
〃Sex organs vary with the species。 It's easy to tell on some； subtle on others。 But； to answer your question； the reason we know all the animals are female is that we literally make them that way： we control their chromosomes； and we control the intra…egg developmental environment。 From a bioengineering standpoint； females are easier to breed。 You probably know that all vertebrate embryos are inherently female。 We all start life as females。 It takes some kind of added effect…such as a hormone at the right moment during development…to transform the growing embryo into a male。 But； left to its own devices； the embryo will naturally bee female。 So our animals are all female。 We tend to refer to some of them as male…such as the Tyrannosaurus rex； we all call it a 'him'…but in fact； they're all female。 And； believe me； they can't breed。〃
The little velociraptor sniffed at Tim； and then rubbed her head against Tim's neck。 Tim giggled。
〃She wants you to feed her；〃 Wu said。
〃What does she eat？〃
〃Mice。 But she's just eaten； so we won't feed her again for a while。〃
The little raptor leaned back； stared at Tim； and wiggled her forearms again in the air。 Tim saw the small claws on the three fingers of each hamd。 Then the raptor burrowed her head against his neck again。
Grant came over； and peered critically at the creature。 He touched the tiny three…clawed band。 He said to Tim； 〃Do you mind？〃 and Tim released the raptor into his hands。
Grant flipped the animal onto its back； inspecting it； while the little lizard wiggled and squirmed。 Then he lifted the animal high to look at its profile； and it screamed shrilly。
〃She doesn't like that；〃 Regis said。 〃Doesn't like to be held away from body contact。 。 。 。〃
The raptor was still screaming； but Grant paid no attention。 Now he was squeezing the tail； feeling the bones。 Regis said； 〃Dr。 Grant。 If you please。〃
〃I'm not hurting her。〃
〃Dr。 Grant。 These creatures are not of our world。 They e from a time when there were no human beings around to prod and poke them。〃
〃I'm not prodding and…〃
〃Dr。 Grant。 Put her down； 〃 Ed Regis said。
〃But…〃
〃Now。 〃 Regis was starting to get annoyed。
Grant handed the animal back to Tim。 It stopped squealing。 Tim could feel its little heart beating rapidly against his chest。
〃I'm sorry； Dr。 Grant；〃 Regis said。 〃But these animals are delicate in infancy。 We have lost several from a postnatal stress syndrome； which we believe is adrenocortically mediated。 Sometimes they die within five minutes。〃
Tim petted the little raptor。 〃It's okay； kid；〃 he said。 〃Everything's fine now。〃 The heart was still beating rapidly。
〃We feel it is important that the animals here be treated in the most humane manner；〃 Regis said。 〃I promise you that you will have every opportunity to examine them later。〃
But Grant couldn't stay away。 He again moved toward the animal in Tim's arms； peering at it。
The little velociraptor opened her jaws and hissed at Grant； in a posture of sudden intense fury。
〃Fascinating；〃 Grant said。
〃Can I stay and play with her？〃 Tim said。
〃Not right now；〃 Ed Regis said； glancing at his watch。 〃It's three o'clock； and it's a good time for a tour of the park itself； so you can see all the dinosaurs in the habitats we have designed for them。〃
Tim released the velociraptor； which scampered across the room； grabbed a cloth rag； put it in her mouth； and tugged at the end with her tiny claws。
Control
Walking back toward the control room； Malcolm said； 〃I have one more question； Dr。 Wu。 How many different species have you made so far？〃
〃I'm not exactly sure；〃 Wu said。 〃I believe the number at the moment is fifteen。 Fifteen species。 Do you know； Ed？〃
〃Yes； it's fifteen；〃 Ed Regis said； nodding。
〃You don't know for sure？〃 Malcolm said； affecting astonishment。
Wu smiled。 〃I stopped counting；〃 he said； 〃after the first dozen。 And you have to realize that sometimes we think we have an animal correctly made…from the standpoint of the DNA； which is our basic work…and the animal grows for six months and then something untoward happens。 And we realize there is some error。 A releaser gene isn't operating。 A hormone not being released。 Or some other problem in the developmental sequence。 So we have to go back to the drawing board with that animal； so to speak。〃 He smiled。 〃At one time； I thought I had more than twenty species； But now； only fifteen。〃
〃And is one of the fifteen species a…〃 Malcolm turned to Grant。 〃What was the name？〃
〃Propsognathus； 〃 Grant said。
〃You have made some propsognathuses； or whatever they're called？〃 Malcolm asked。
〃Oh yes；〃 Wu said immediately。 〃pys are very distinctive animals。 And； we made an unusually large number of them。〃
〃Why is that？〃
〃Well； we want Jurassic Park to be as real an environment as possible…as authentic as possible…and the propsognathids are actual scavengers from the Jurassic period。 Rather like jackals。 So we wanted to have the pys around to clean up。〃
〃You mean to dispose of carcasses？〃
〃Yes； if there were any。 But with only two hundred and thirty…odd animals in our total population； we don't have many carcasses；〃 Wu said。 〃That wasn't the primary objective。 Actually； we wanted the pys for another kind of waste management entirely。〃
〃Which was？〃
〃Well；〃 Wu said； 〃we have some very big herbivores on this island。 We have specifically tried not to breed the biggest sauropods； but even so； we've got several animals in excess of thirty tons walking around out there； and many others in the five… to ten…ton area。 That gives us two problems。 One is feeding them； and in fact we must import food to the island every two weeks。 There is no way an island this small can support these animals for any time。
〃But the other problem is waste。 I don't know if you've ever seen elephant droppings；〃 Wu said； 〃but they are substantial。 Each spoor is roughly the size of a soccer ball。 Imagine the droppings of a brontosaur； ten times as large。 Now imagine the droppings of a herd of such animals； as we keep here。 And the largest animals do not digest their food terribly well； so that they excrete a great deal。 And in the sixty million years since dinosaurs disappeared； apparently the bacteria that specialize in breaking down their feces disappeared； too。 At least； the sauropod feces don't depose readily。〃
〃That's a problem；〃 Malcolm said。
〃I assure you it is；〃 Wu said； not smiling。 〃We had a hell of a time trying to solve it。 You probably know that in Africa there is a specific insect； the dung beetle； which eats elephant feces。 Many other large species have associated creatures that have evolved to eat their excrement。 Well； it turns out that pys will eat the feces of large herbivores and redigest it。 And the droppings of pys are readily broken down by contemporary bacteria。 So； given enough pys； our problem was solved。〃
〃How many pys did you make？〃
〃I've forgotten exactly； but I think the target population was fifty animals。 And we attained that； or very nearly so。 In three batches。 We did a batch every six months until we had the number。〃
〃Fifty animals；〃 Malcolm said； 〃is a lot to keep track of。〃
〃The control room is built to do exactly that。 They'll show you how it's done。〃
〃I'm sure；〃 Malcolm said。 〃But if one of these pys were to escape from the island； to get away 。
〃They can't get away。〃
〃I know that； but just supposing one did 。 。 。〃
〃You mean like the animal that was found on the beach？