A look at which animals get the giggles; what would cause the sea lions of San Francisco to mysteriously swim away all at once, manta rays that synchronize swim.

A look at why a herd of wild elephants check into the same hotel every year and what is causing giant bubble rings off the coast of Portland, Maine.

A look at why 25,000 honey bees would swarm a hot dog stand in the middle of Times Square; what would cause a healthy bat to hunker down in the snow; how is this crayfish super species threatening to take over the world.

A look at why crows leave gifts in suburban Seattle; how it's possible a shark can be older than America; and who is making the mysterious crop circles at the bottom of the sea in Japan.

A look at what causes a pair of giraffes to turn white; why are millions of birds creating crazy patterns; why would the world's fastest land animal give up the hunt.

A look at how bats avoid bumping into each other at night; why a bottlenose dolphin seeks out the help of a scuba diver; are cicadas expert mathematicians.

A look at how a dung beetle standing on its head can roll a ball in a straight line; if egrets ever regret hanging out next to hungry alligators; and what ghostly creature was caught on camera 3000 feet below the ocean's surface.

A look at why a seal throws an octopus at a kayaker; why a moth is drinking from the eye of a bird in the Amazon jungle; what surprising creature has been leaping out of the Irish sea.

A look at what could swallow 50-foot trees in seconds, and what animal has changed the face of Yellowstone.

A look at where to go to find an enchanted underwater forest; some Mexican rattlesnakes have lost their rattle; an Indian elephant.

A look at why a leopard let its dinner escape; an ominous dark mass looming over an Icelandic lake; some scorpions glow in the dark.

A look at why goats risk life and limb to climb an almost vertical dam wall; a zebra has no stripes; a school of fish swarm a diver.

A look at why some spiders disco dance; a mysterious creature is preying on Europe's sheep; a whole town is engulfed by bubbling foam.

A look at what would cause a ferocious tiger shark to cuddle up with a diver and why pigs are swimming in the Caribbean; and what mysterious blobs have washed up by the thousands on the shores of Oregon.

A look at how a moose get stuck in an apple tree; why a crow is snowboarding on a jam jar lid; and whether Yellowstone's super volcano is about to erupt.

A look at if its possible that a snake could exist totally undetected; what brought this big cat fight to ear piercing decibels; and why is this lone dolphin getting muddy.

A look at how spiders covered a town in webs overnight and why a lake in South America is the lightning capital of the world.

A look at what animals are breaking into thousands of cars every year, how ants form a ten-foot bridge using only their bodies, and why did the fish cross the road.

A look at what could make an animal vanish into thin air, what could cause the sea to take on an eerie glow, and what event would bring killer whales together in huge numbers.

A look at how a bird could sing without using its voice and how an octopus could simply disappear from his aquarium tank.

A look at the possibility that zombie spiders are real and why would a pod of beluga whales adopt a unicorn of the sea.

English naturalist Chris Packham explores some of the strangest natural events to be caught on camera in this docuseries. Assisted by scientists and experiments, Packham explores the secrets behind bizarre science, crazy weather and medical marvels. Using footage taken by eyewitnesses and news crews, the host attempts to decipher the truth behind each scene. Some of the incidents under scrutiny are unusual animal friendships, towns under the siege of thousands of flying insects and extraordinary mating calls that have kept people awake at night.

Searching for the world's strangest creatures.

Experts weigh in on some of the strange moments in history.

Sir David Attenborough narrates this critically acclaimed series that dives deep into the marine environment of Planet Earth. Although two-thirds of the world's surface is covered with water, scientists know less about the oceans than they do about the surface of the moon. This limited series travels from various coasts to the poles to examine watery denizens ranging from the gigantic blue whale to microscopic coral polyps.