Question: What was the key discovery made by Jan-Hendrik Hehemann, and why was it considered so profound? Need Assignment Help? Question Answer a. All humans share identical microbiomes, indicating strong genetic control b. Gut microbes are inherited only from parents, showing strict vertical transmission c. Marine bacteria transferred genes to human gut bacteria, allowing digestion of seaweed, revealing cross-ecosystem horizontal gene transfer d. Human gut bacteria can produce antibiotics, demonstrating microbial competition