Extreme Animal Weapons

From lobster claws and dog teeth to bee stings and snake fangs, every creature depends on a weapon. But some are armed to extremes that make no practical sense—whether it's bull elks with giant 40-pound antler racks or tiny rhinoceros beetles with horns bigger than their body. What explains giant tusks, horns, and claws that can slow an animal down and even impair health and nutrition? NOVA investigates the riddle of outsize weaponry and uncovers a bold new theory about what triggers an animal arms race. In creatures as varied as dung beetles and saber-toothed tigers or shrimp and elephants, the same hidden factors trigger the race and, once started, these arms races unfold in exactly the same pattern. Join scientists as they crack the secret biological code that underlies nature's battleground.
Trailer
Recently Updated Shows

Ghosts
Samantha and Jay throw caution to the wind when they convert their recently inherited country estate into a bed-and-breakfast. Call it mislaid plans. Not only is the place falling apart, but it's also inhabited by spirits of previous residents -- whom only Samantha can see and hear. Ghosts spins the funny, heartfelt story about a newfound dream that reveals connection and self-discovery aren't just for the living.

Grey's Anatomy
The doctors of Grey Sloan Memorial Hospital deal with life-or-death consequences on a daily basis -- it's in one another that they find comfort, friendship and, at times, more than friendship. Together they're discovering that neither medicine nor relationships can be defined in black and white. Real life only comes in shades of grey.

Law & Order: Special Victims Unit
In the criminal justice system, sexually-based offenses are considered especially heinous. In New York City, the dedicated detectives who investigate these vicious felonies are members of an elite squad known as the Special Victims Unit. These are their stories.

FBI
FBI is a fast-paced drama about the inner workings of the New York Field Office of the Federal Bureau of Investigation. These first-class agents, including Special Agent Maggie Bell and her partner, Special Agent Omar Adom 'OA' Zidan, bring all their talents, intellect and technical expertise on major cases in order to keep New York and the country safe.

Tracker
Tracker features lone-wolf survivalist Colter Shaw, who roams the country as a "reward seeker," using his expert tracking skills to help private citizens and law enforcement to solve all manner of mysteries while contending with his own fractured family.