Curious Kids^[1] is a series for children of all ages. If you have a question you’d like an expert to answer, send it to This email address is being protected from spambots. You need JavaScript enabled to view it.^[2]. Why do people hate people? – Daisy, age 9, Lake Oswego, Oregon Have you ever said “I hate you” to someone? What about using the “h-word” in casual conversation, like

How did your heart form? What triggered your first heartbeat? To this day, the mechanisms of human heart development remain elusive.

Researchers know the heart is the first organ to fully function^[1] in the growing human embryo. It begins as a simple tube that starts to pump blood by the fourth week of gestation. By the ninth week, the...

Algorithms are a staple of modern life. People rely on algorithmic recommendations to wade through deep catalogs and find the best movies, routes, information, products, people and investments. Because people train algorithms on their decisions – for example, algorithms that make recommendations on e-commerce and social media sites –...