"Life ... uh ... finds a way."

All the animals in Jurassic Park are female, so where did the fertilized eggs come from?

On the tour, the film said they used frog DNA to fill in the gene sequence gaps; they mutated the dinosaur genetic code and blended it with that of a frog’s. Now, some West African frogs have been known to spontaneously change sex from male to female in a single-sex environment…

Some of the DNA used to recreate them was from frogs, and some frogs can change gender. This was the guess made by Sam Neil’s character in the first film.

In the movie it’s mentioned that there are some frogs, or turtles, or something (I forget) that have been known to change sex in the absence of males or females in the population (I have no idea if that’s factual or not). It’s also mentioned that the dinosaur’s DNA is mixed with frog of some kind. Therefore, the dinos “found a way.”

This is hinted at early in the movie when Dr. Grant only has two female seat-belt buckles and he makes it work.

It’s frogs all the way down.


The frog thing was explained much better in the book. I probably shouldn’t have read it before seeing the film.

But if some of the dinosaurs can change their gender then you don’t have an all-female population of dinosaurs.

So Hammond and Wu were lying to Alan & Ellie & Malcolm? And they deliberately put little kids on a tour near aggressive male dinosaurs?

I don’t know why they were breeding carnivores at all. They’re just going to want to eat your as-expensive herbivores, which frankly are impressive enough in themselves to sell tickets.

One element from the novel that cracked me up was the recurring fear that the dinos were going to reach the South American mainland and, I guess, take over the world or something, hence the repeatedly-referenced contingency plan of using an Andromeda Strain-type nuke to “solve” the problem. So dinos get to the mainland… big fucking deal. Just announce to the world that there are dinosaurs in South America and within days the continent will be teeming with overly rich/bored big game hunters who will show up with infra-red scopes, helicopters and .50 caliber rifles and they’ll readily return the dinos to extinction. Even a lot of the hunters getting killed in the attempt will just increase the appeal of having a stuffed and mounted velociraptor head in your expensively-furnished man-cave.

The scientists thought all of the dinosaurs were female. It didn’t occur to them that the frog DNA might allow some dinosaurs to change into males. In the book, the dinosaurs are counted to make sure none escaped. At each counting, there were 300 dinosaurs. But…

Whoever did the programming for the counting program made a mistake. The scientists expected to have 300 dinosaurs. So the programmer wrote the program to count up to 300 dinosaurs. Once it hit 300, it stopped counting. So the animals were breeding and nobody knew it.

As I recall, this was not shown in the movie.


You know, that never sat right with me because it’s so contrived, from a coding point of view. As in, you have to add useless code for the count to stop at 300, instead of just “If NonTalliedDinosaur()=true then TotalCount++ ; printf TotalCount” which is what any slacker, I mean coder, would do even if they had zero foresight or inkling the dinosaurs might start bumping cloacas on the sly. It’s just pointless to add a hardcap to the count ! It doesn’t speed up the count or make it run smoother or nothing. It merely allows dinosaurs to reproduce on the down low.

Well that one’s easy : yes it’s kinda cool to see alpacas and long-eared goats ; but people who go to the zoo are there for the bloody tigers, Brenda. Similarly while herds of hadrosaurs are cool and all, the park’s logo is a fucking T-Rex. Because T-Rex was hella cool before we figured out it most probably was a carrion feeder.

Also why carnivore feeding times are typically publicized in mundane zoos. Panem et circenses.

Well, it introduces logistics problems, aggravated by being on an island. Can you bring in enough cattle and goats to keep your carnivores fed? I suppose if a section of the island was put aside just for breeding and raising animals for food, you might be able to cut costs a little, but how much meat did they think a T-Rex needed every week? If it was the equivalent of a two-ton stegosaurus, you’re gonna go through a lot of cows.

Messy business, is show.

It doesn’t even need the dodgy ‘frog DNA allows them to change sex’ explanation. In 2006, a Komodo Dragon at Chester zoo laid eggs. It was female, and it’d never been in the same enclosure as a male. They looked like decent eggs, so staff stuck 'em in the incubator. Several hatched. Testing confirmed all the DNA was from the mother.

Until that point, despite being a well known species, no one had any idea that Komodo Dragons were capable of parthenogenesis. They’re hardly the only reptile species that are either.

Over the long haul, sure, but it’s years before the business model needs carnivores, they could have made a fortune dialing in the park with veggiesaurs and then expanded, but that wouldn’t make as good a movie.

Not only can female Komodo dragons spontaneously produce viable eggs, they can also produce males in that manner (they, obviously, use a different sex-determination system than mammals do).

The big problem with that plan is that like every single “Government pays people to kill invasive species” program ever implemented you’ll have people killing non-dinos either out of confusion or malice and wind up with an entirely different ecological catastrophe. Plus you might wind up with people grabbing dinos alive for various reasons. It’s one of those things where it’s much simpler to just firebomb the island if things go out of control.

I don’t think it’s that contrived. Someone is brought in to write a program that reads the number of dinosaurs, and is told there are 300 animals. (I don’t remember how they were detected so that they could be counted with a computer.) So the programmer writes DO WHILE DCOUNT LE 300… [Read sensor data and add one for each unique one]… END-DO… DISPLAY DCOUNT ’ dinosaurs counted.’