What does it do?
Only the red rectangle is capable of reproduction. Both rectangles have
genes on the back. A gene is a pair of an animal gadget and a number
representing the dominance of the gene. The sample genes here just change the
appearance, width, or height.
When the red rectangle first touches the blue rectangle and the right mouse
button is depressed then the rectangles mate. Reproduction involves generating
a gamete (by randomly choosing between genes inherited from the mother and
father) for each parent, combining them, producing and adding a new
"creature". The genes are then expressed by selecting the dominates genes and
adding them to the back of the picture.
How do I use it?
This demonstration uses a little hand as a tool for dragging things
around. Click the left mouse button to select an object, and drag one of the
rectangles so it touches the other. Clicking the left mouse button again will
stop dragging. Then press the right mouse button and watch a child emerge. To
get another child move the rectangles apart and move the hand away from the
red rectangle to reset it. Then put together two creatures again and press the
right mouse button to get another child.
How does it work?
Briefly explained above.
What can I use it for?
Reproducing Mendelian genetics and more.

This example includes a gene that, if functional, ensures that the offspring
can reproduce.