In Medium, non-members can 3 articles for free per month. Beyond that, membership is required. But opening the article in a guest or incognito browser can bypass the paywall.

Alternatively, you can subscribe to get an email from Microbial Instincts (https://medium.com/microbial-instincts/newsletters/microbial-instincts), where I sent monthly newsletters that contain friend links (no paywall) to all the articles published that month.