“You have a better understanding of living creatures and their strengths and weaknesses. You get a one-time bonus of +10% to Doctor, and you do +5 damage per attack to living creatures.”— Fallout 2 description
“Living Anatomy allows you to see the health and Damage Threshold of any target. It also gives you a +5% bonus to damage against humans and non-feral ghouls.”— Fallout: New Vegas description
You have a better understanding of the strengths and weaknesses of living creatures. You gain a +2 damage bonus against all living creatures and when you score a hit against living creatures, your attack roll is increased by 5 for purposes of determining critical hits.