Hot Peppers and Artificial Selection - Kesler Science Weekly Phenomenon &  Graph

The world of hot peppers is WILD. In 2007, the hybrid Ghost pepper from India was the hottest pepper in the world. It was dethroned by the infamous Carolina Reaper pepper in 2013. In October 2023, a new pepper called "Pepper X" claimed the world title - it's about 1000 times hotter than a jalapeno!  🥵

This is a great connection to artificial selection that students might enjoy because of shows like Hots Ones. Who doesn't like to watch celebrities cry over their chicken wings? 😆 Using the same process that brought us goldendoodles, pepper growers create hybrid varieties of peppers that combine the best characteristics of two types of peppers. They also select the hottest peppers from one generation and keep those seeds to grow the next generation. It takes about 10 generations before an unusual pepper trait, like extreme heat, becomes a consistent trait in the population.

Check out the graph below to see how artificial selection has affected the heat levels of peppers!

If I were going to share this graph with my students, here are some questions I might ask them:

💡Which peppers have less than 1 million Scoville heat units? Red savina habanero, habanero chili, tobasco pepper, jalapeno pepper and bell pepper all have less than 1,000,000 Scoville heat units. 

💡About what is the difference in heat units between Trinidad Moruga Scorpion pepper and Pepper X? Pepper X has about 2,600,000 heat units while the Scorpion pepper has about 1,500,000 heat units. This difference is roughly 1,100,000 heat units. 

💡How do Habanero Chilis compare to the Carolina Reaper in spiciness? The Habanero Chili has about 300,000 heat units while the Reaper has 2,500,000 heat units. The Reaper is about 10x more spicy than the Habanero. 

Want great phenomena, graphs, and more delivered straight to your inbox each week?

Join the Kesler Science mailing list and we'll send you the Kesler Science Weekly Phenomenon & Weekly Graph, plus sales info, product highlights, and freebies!

You can also sign up for our weekly newsletters for elementary and science teachers, because everybody deserves a little encouragement.