Sure lactase is the enzyme used to break lactose down to glucose. There is a competitive advantage to retaining lactase production in the digestive tract for some species, but the issue is complex; pregnant lactating mothers are unsustainably taxed and average lower reproductive rates than non lactating mothers. Evolution has opted for the cessation of lactase production after infancy every species. Most people don’t effectively process lactose, but the ecoli bacteria in the large intestine due process it and multiply, causing the undesirable after effects. nostr:npub18myhrpdny5d58elt4skhyqfrm2shawekgzu8jetug8jypkhlhzts4hqm0g