Show you can do real investigation.
In research fields, evidence means investigation you can show:
- Undergraduate research or lab assistant work.
- Conference posters that summarize a question, method, and result.
- Publications, eventually — but a clear poster or write-up is a strong start.
Try it: pick a science question that interests you, find two reliable sources about it, and write a short summary of what's known, what's still uncertain, and what experiment could push it forward. That's the seed of real research.