How to Play 🎮

Your goal is to sort images into three categories. The best way to learn is by trial and error, but here are some general clues to get you started:

• Hard Sweep: Usually shows one long, solid pattern of just red and white at the top.Examples▶
• Soft Sweep: Tends to have several different horizontal bands with chunks of black.Examples▶
• Neutral: Typically lacks any strong banding patterns.Examples▶

Don't be discouraged if you get a wrong answer. Sorting these images is an ongoing focus of evolutionary biology researchers.

The Science Behind the Images 🧬

These messy images are actually visual maps of ancient human DNA. Each row is one person’s genetic sequence, and a red or black pixel shows a specific version of a gene. The white space is missing data, much of which results from the DNA breaking down over thousands of years.

The patterns you're sorting are called “selective sweeps,” and they tell a story about evolution:

• A Hard Sweep is where a single, highly beneficial mutation appeared in one ancestor and was so advantageous it quickly spread throughout the whole population.
• A Soft Sweep is where several individuals already had a beneficial gene, and this trait rose in popularity from multiple sources at once.
• Neutral is where no strong selection is happening.

Your Mission

The Garud Lab at UCLA uses computer vision techniques to find these patterns, but to know if our machine learning models are performing well, we need your help. By playing, you are creating a vital human benchmark for science. Please feel free to submit your score to the leaderboard!