There actually is a game really similar to what you're asking, but sadly it probably isn't a game that your son would enjoy.But Cell Lab is a sort of a puzzle game where you are given an environment, and you have to design an organism that can survive in there.The organisms exist of a few 'cells'. Each of these cells have a function: eat food, collect sunlight, store energy, swim, attack other cells, float, and more. So for example you can have a cell that splits up in a swimming cell and an eating cell, and then swims around eating food.But the most interesting thing is the sandbox mode: in here can organisms actually evolve, in the 'scientific' way.

• Free Spore Creature Creator

Each time a cell splits, it mutates slightly, and if this makes the organism more successful it will outcompete the others. This way the organisms will adapt to their environment, and sometimes even simple ecosystems can form.

You can also insert your own organism, and watch how it competes with the others. Sadly the sandbox mode won't create diverse organisms, there is usually just one 'solution' to a specific environment so only one type of organism will usually form. But maybe I am just not creative enough when creating an environment.Linkme: Cell Lab. :TechnoSphere was an online digital environment launched on September 1, 1995 and on a computer at a university. TechnoSphere, created by and Gordon Kelly, was a place where users from around the globe could create creatures and release them into the environment, described by the creators as a 'digital ecology.' Earlier incarnations of TechnoSphere didn't have the advantage of web-accessible 3D graphics, but was still governed by and similar that determined each creature's unique behavior based on their components and interactions with each other and their environment.

Free Spore Creature Creator

This online program was one of many digital simulations that evolved as the began to grow. Many museums and classrooms found the tool to be a valuable complement to learning material on.

The experiment operated online until 2002 and was unavailable until January 15, 2007 when it was launched again but as of November 2012 is again off-line.- Part of the fractal landscape of TechnoSphere. The trees were positioned with a seeding algorithm created by Gordon Selley.Interesting: Parent commenter can.

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