##  [Janzen–Connell Hypothesis](/index.php/janzen-connell-hypothesis) 

  ##  [Janzen–Connell Hypothesis](https://commerce.quantumdictionary.io/janzen-connell-hypothesis-0) 

  

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**Commerce, Trade & Industry Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A biogeographic hypothesis that host‑specific natural enemies (e.g., pathogens, herbivores) cause elevated mortality of conspecific offspring at short distances or high local densities near parent plants, producing negative distance‑ or density‑dependent recruitment that reduces local dominance and helps maintain plant species coexistence.