How do we explain all the forms of life we see around us today? Compare the time when there was no life on earth with today, in which we see multitudes of species of which there are many still to be discovered. Put a black box between these two points in time. The black box has only one function - to get from there to here. To get from no life to life as we know it now. Creationists say the inner workings of the black box are rather simple: God created all life. Intelligent Design proponents say some intelligence "designed" all the life around us, including all that has come before and since gone extinct. Scientists who give us the Theory of Evolution say life evolved from an early self-replicating mechanism that evolved and branched out over millions of years.
The difference between these three views is that two of them leave the black box opaque, while the third is making it more transparent every day. Creationists and IDists have no way to support their particular views other than to attack evolution. The Discovery Institute has frequently linked evolution to eugenics (most recently regurgitated in a podcast here). If evolution was a person, this would amount to nothing more than an ad hominem attack. They have no real science to support them. But if they think they do, then let them answer this challenge:
(links: Atheist Media Blog, Pharyngula, Thunderf00t, and C0nc0rdance)