The evidence for natural selection is presented as a random variation of a characteristic allowing a particular strain of organism to survive with a higher probability of successful reproduction. Population change over a short period is...

That little pink bud in the inside corner of your eye is actually a vestigial eyelid! Find out more about the plica semilunaris, in a short video that explains why vestigial structures hang around.

Charles Darwin's work, On The Origin of Species, fundamentally changed the study of science. Using clips from an author talk, young historians connect the scientific ideas behind evolution to American history. Afterward, they consider:...

A crocodile with hooves and razor-sharp teeth was really a thing—and there is proof. A video lesson from the PBS Eons series presents the fossil evidence and explores the reasons for the adaptations of the unique reptile. Scholars see a...

Overcoming pupil misconceptions is much harder than teaching a new topic. Anticipate misconceptions to avoid having to reteach and relearn by showing a lesson resource from the Good Thinking PD series that highlights common mistakes. A...

The concept of evolution changed the way scientists view the world. Part of the PBS Ions series, a thorough video lesson explains the process of evolution by exploring the work of scientists like Charles Darwin and Gregor Mendel. The...

Bears come in many different shapes and sizes. Follow the evolution of the prehistoric bear through time in an episode from the PBS Eon series. The narrator discusses the evolution of the bear by examining adaptations and their...

Bigger and faster is not always better! Explore the characteristics of the ancestors of the current scorpions with an intriguing video. Scholars learn the connections of these changes to the environment of the different time periods.

Are you afraid of holes? Believe it or not, some people are! An interesting video explores the science behind trypophobia, or the fear of small holes. Viewers learn about the scientific difference between fear and disgust and identify...

From cute little birds to giant aviary specimens—all animals evolve! Learn how natural selection on an isolated island in the Mediterranean encouraged animals species to increase in size. The narrator discusses fossil evidence that...

Although some may be crocodile tears, crying is a distinct honor humans hold. Scholars learn the biological reason behind the emotional crying in a video lesson. The lesson instructor explores the anatomical and psychological connections...

Human traits trace back to simpler species—such as chickens, for example. Using the human genomes, scientists connect these traits to their ancestral origins. A video presentation highlights the structure of human DNA and makes a...

There's nothing regular about them—irregular verbs turn out to be the most common verbs in the English language. Through an analysis of data, learners discover that Zipf's Law describes the patterns of word usage. 

Can competing biological theories both be correct? Explore the two theories many scientists believed were opposing in a Crash Course History of Science video. The narrator covers both Darwin's and Mendel's genetics theories, the...

From the top of the food chain to extinction, follow the life of the megalodon! An episode in the PBS Eon series describes the evolution of the ancient species and its eventual extinction. The narrator discusses the fossil evidence and...

Would you believe the Midwest region of the United States was once the Western Interior Seaway? An interesting presentation from the PBS Eons series describes the geography of the ancient seaway and the species that lived there. The...

Discover the versatility of the sloth species—at least what it once was! Scholars examine the history of the evolution of the sloth in a segment of the PBS Eons series. They learn that the current-day view of the sloth is one of a...

The first video in a five-part series on Evolution and Speciation introduces four types of evolution and addresses common misconceptions. In addition, viewers learn about topics current understanding of science does not fully explain.

The rock pocket mouse exists either with light colored or dark colored fur. As their habitat changes from sandy desert to lava flows the prominence of each color fur also changes. Viewers compare the visibility of each mouse's fur color...

Texas short-horned lizards shoot blood out of their eyes to deter predators. The unique adaption allows them to thrive in a hostile environment. Pupils learn more about this and other adaptations of plants, animals, and humans in the...

Viewers l earn about the rise and fall of social Darwinism, eugenics, and flawed science during the 23rd episode of the Crash Course History of Science video series. The video covers if awesomeness is hereditary, the invention of birth...

Charles Darwin studied many species, but he also hindered their continued study by eating his specimens. Like many sailors, he enjoyed the taste of the Galapagos tortoise so much for many years that no ship made it all the way back to...

G.H. Hardy and Wilhelm Weinberg created a mathematical formula to predict genotype frequencies. Observe a simulation of the Hardy-Weinberg equation using pocket mice. Scholars consider the selection coefficient, selective advantage, and...

Different regions of the world have greatly varying rates of lactose tolerance. Learn why this mutation spreads in some populations and not others with an educational video. Viewers consider the relationship with natural selection in...