Claude Fable 5 blocks basic biology to stop bioweapons

anthropic's claude fable 5 refuses to answer basic biology questions, blocking queries about cell membranes or asthma medication despite claiming to be the most powerful model available. a spokesperson explained this intentional tradeoff: preventing malicious actors from using the model for risky biological research required 'overly conservative' safeguards that block most biology work. while filters on chemistry and cybersecurity are lighter, the strict biology limits force users back to the previous claude opus 4.8 model.