The crow stared at the screen, as it had many times before. Six shapes appeared. Five were neat, balanced, regular; one was ...

Scientists tested crows on their ability to recognize “geometric regularity,” a skill previously assumed to be unique to ...

Crows in a lab were able to distinguish shapes that exhibited right angles, parallel lines, and symmetry, suggesting that, ...

Narrator: What’s important to understand is that geometry has rules, has facts you need to know. Here’s a rule you probably know: that a shape with 4 right angles and 4 equal sides is a square!

Before reading this guide, it may be helpful to read the guides from Module 1 on the properties of angles and the properties of 2D shapes. The sum of the angles inside any polygon can be found by ...