WEIQ-DT

The five mass extinctions; what evolutionary theory says about the world people will leave behind.

Four people on four continents face environmental change driven by climate change; as resources grow scarce, they witness shifts in wildlife behavior.

An Edgar Allan Poe daguerreotype; a Teco collection circa 1905; a 1907 Frank Lloyd Wright archive.

Thoreau returns to society, taking on roles as surveyor, scientist and abolitionist, and makes two more Maine trips; Thoreau writes with renewed energy as he faces a lifelong illness.

Actresses Debra Messing and Melanie Lynskey explore the stories of their ancestors whose bold decisions reshaped their families.

Romania's capital, Bucharest; Transylvania's fortified churches, cobbled merchant towns and castles; Maramures region of Romania.

A variety of exercises to strengthen postural and core muscles, improve balance, mobility and range of motion; finger and wrist exercises; tai chi; stretching mobilization exercises to improve gait and mobility; feet exercises.

Roaring like a lion; strengthening the vocal cords; massaging the thyroid and facial muscles.

On their annual laundry day, the Kratt brothers disagree on whether blue oceans or green forests are better; Aviva demonstrates how oceans and forests work together.

Pinkalicious and Peter are surprised when they find a monkey outside their treehouse; while their new friend is lots of fun, she's also a bit of a trickster -- and pretty messy.

It's an exciting day for Lily and her family when they move into their new house.

Daniel has many activities he wants to do with Juan Carlos, but Mom reminds him to ask his guest what he wants to do; Daniel can't wait to show Juan Carlos the Clock Factory.

Phoebe and Jay set a new record for the longest paper airplane fight; Phoebe and Jay learn how to build a stable pillow fort.

Abby, Big Bird and Cookie Monster play against Gabrielle, Zoe and Elmo in I Wonder If We Can Use This, a game where they figure out if items can be used for something.

Malik enters the Undergroundborhood to retrieve JunJun's favorite ball; the Wombats cheer up Buckley with balloons.

Duck Duck learns how to fix her broken bookcase; Donkey welcomes Greeble the Treeble to Someplace Else.

Rosie learns about a surprise for a sister, and tries to find out who that sister is; Rosie looks for someone to be her twin.

Honeybees disturb Elinor, Art, Olive and Koa during their picnic in the forest; the kids work together to move their dirt bike path so turtles can get to the water.

Carl takes his friends on an "Amazing Smell Tour of Fuzzytown," but Lotta doesn't agree with Carl's list of the best smells; Carl and his friends go on a camping trip.

Everett faces his fear of water by taking a swimming lesson; Lyla doesn't want Miss Emmaline to move.

Louis Pasteur helps Xavier with his volcano experiment project; Rachel Carson helps Brad figure out a way to help butterflies migrate.

Alma wants to hang out with Eddie's friends, but doesn't like it when she starts to feel like a little kid; Junior becomes everyone's pretend little brother.

The team learns about friction and how to slow down a moving object when a masked villain takes over the Mobile Unit van's computer.

The kids create a new game called Mollyball; Molly convinces a travel guide writer to visit Qyah, so the village can be added to the guidebook.

On their annual laundry day, the Kratt brothers disagree on whether blue oceans or green forests are better; Aviva demonstrates how oceans and forests work together.

From snowy owls in the high Arctic to honey buzzards raiding hornet nests in Taiwan, a look at the extreme ways in which raptors conquer the toughest habitats on Earth.

Understanding how the brain shapes reality, including the tricks and shortcuts the brain takes to keep a person alive; with neuroscientist Heather Berlin.

Appraisals from the grounds of Winterthur Museum, Garden & Library in Delaware include a valuation of a $125,000 family treasure.

Co-anchors Amna Nawaz and Geoff Bennett and correspondents offer in-depth analysis of current events.

Laying out the wiring for radiant floor heating; custom kitchen cabinets; work is done on the built-in bookcase.

Upgrading shutters in a historic New Orleans neighborhood; how to read fertilizer labels and choose between organic and synthetic options; upgrading battery-operated smoke detectors to a hardwired combo alarm system.

Recipes for green bean casserole, yeast rolls, and banana pudding. Chris Spear offers tips for preparing a juicy and delicious ham.

The country sextet Flatland Cavalry.

A look at today's action in the Alabama Legislature.

Twenty-four hours a day, the latest national and international stories as they break.

Mauro paints a baby's nursery using zero VOC paint; Richard tests out a new dryer that uses a heat pump to dry the clothes; Tom and Kevin build a record player stand out of oak plywood.