I don't speak Latin. It's a dead language. It killed the Romans, and now it's killing us. - Kent Hovind

Why would any organism want to reproduce more of its own kind when that's only going to increase competition for the food supply? Why didn't they instead evolve the ability to live forever and then be happy?

Eight simple steps of what I think caused the Flood and explain all these strange phenomena on the planet. Then we'll go into a little bit more detail and then we'll close this down.
1. Noah and the animals got safely in the ark.
2. A 300 degree below zero ice meteor came flying toward the earth and broke up in space. As it was breaking up, some of the fragments got caught and became the rings around the planets. They made the craters on the Moon, the craters on some of the planets, and what was left over came down and splattered on top of the North and South pole.
3. This super cold snow fell on the poles mostly, burying the mammoths, standing up.
4. The dump of ice on the North and South pole cracked the crust of the earth releasing the fountains of the deep. The spreading ice caused the Ice Age effects. The glacier effects that we see. It buried the mammoths. It made the earth wobble around for a few thousand years. And it made the canopy collapse, which used to protect the earth. And it broke open the fountains of the deep.
5. During the first few months of the flood, the dead animals would settle out, and dead plants, and all get buried. They would become coal, if they were plants, and oil if they're animals. And those are still found today in huge graveyards. Fossils found in graveyards. Oil found in big pockets under the ground.
6. During the last few months of the flood, the unstable plates of the earth would shift around. Some places lifted up; other places sank down. That's going to form ocean basins and mountain ranges. And the runoff would cause incredible erosion like the Grand Canyon in a couple of weeks.
7. Over the next few hundred years, the ice caps would slowly melt back retreating to their current size. The added water from the ice melt would raise the ocean level creating what's called a continental shelf. It would also absorb carbon dioxide out of the atmosphere which allows for radiation to get in which is going to shorten people's life spans. And in the days of Peleg, it finally took affect.
8. The earth still today shows the effects of this devastating flood.

God not only told them what to do and how to live before the Flood, He also told them what to eat. He gave them a perfect diet. God said, I want you to eat the herbs. Kids, eat your vegetables, the fruit, and the seeds (Genesis 1:29). We don't do that much. We eat the hamburger, french fries, and Coke. God said eat the fruit, vegetables, and seeds. When you eat the fruit, you should eat the seed. When you eat a peach, eat the seed. You say that thing's hard. Well, crack it open with a hammer. The seed is inside the hull, okay. [...] Now be sure to get organically grown seeds, not the ones grown on steroids and pesticides. But the seeds contain a bitter substance called cyanide. That'll give you a pucker that'll last about an hour and a half. [...] But these seeds contain a vitamin called vitamin B-17 which is half cyanide. You say, oh, that's poison. Oh, it's not either! [...] So the cyanide found in the seeds is mixed with benzaldehyde. Both are poison, but together they're harmless. Until they bump into a cancer cell!