If you walked into a science class today and opened your notebook, the topic matter might be slightly different from when you were in school.

Our scientific knowledge base is constantly expanding and evolving. New discoveries or investigations frequently lead to revisions in previous beliefs, and in some cases, invalidation. As a result, some of the "facts" you learned in school may no longer be accurate.

Dinosaurs, for example, didn't likely appear as they did in your textbook. The history of Homo sapiens isn't as straightforward as you may think. And a lot of what you learned in your health classes about nutrition and exercise has been disproved.

Here are some scientific facts that are no longer true that you may have studied in school.

Science Times - Mangled Trilobite Discovered in Czechia, Possibly Attacked by a Giant Sea Scorpion 450 Million years Ago
(Photo: Gary Todd on Wikimedia Commons)
Fossil Trilobites

Nobody Knows What Caused the Dinosaurs' Mass Extinction for Now

Scientists used to be baffled as to what caused the dinosaur extinction. National Geographic shared suggestions ranging from low dino sex drives to a world overrun by caterpillars.

However, in 1978, geophysicists discovered Chicxulub, a 6-mile-wide crater on the Yucatan Peninsula created by the asteroid that most likely killed the dinosaurs.

Since then, Business Insider said new information regarding the asteroid's collision had been discovered. The collision resulted in a mile-high tsunami, wildfires, and the emission of billions of tons of sulfur into the atmosphere. Another Business Insider report said it obliterated the sun for years.

ALSO READ: Dino-Killer Space Rock Left Fossilized Megaripples of Mile-High Giant Tsumami

Sixth Sense and More? Sure?

Taste, touch, sight, hearing, and smell are just a few of the ways we perceive the environment. Accelerometers, located in the vestibular system within our ears, detect movement. Fluid moving through microscopic tubes deep inside our ears allows us to perceive movement and employ our sense of balance. Make yourself dizzy, and The Conversation said it is this sensation that you are perplexed about.

We may feel our blood become acidic when we hold our breath because carbon dioxide dissolves in it and forms carbonic acid. Not to mention temperature, pain, and time sensations, among many others, which enable us to respond to what is happening within us and in the environment around us.

Humans First Reached North America 13,000 Years Ago by Crossing the Bering Land Bridge? NOPE!

Archaeologists have unearthed traces of human existence dating back thousands of years. Business Insider experts have discovered nearly 2,000 stone tools, ash, and other human artifacts in a high-altitude cave in Mexico. Some of which date back 30,000 years.

Science Magazine said scientists discovered roughly 14,000-year-old petrified human feces in an Oregon cave. Between 14,500 and 19,000 years ago, experts (per "New Archaeological Evidence for an Early Human Presence at Monte Verde, Chile") discovered artifacts from a colony in southern Chile. Archeologists, according to "Earliest Human Presence in North America Dated to the Last Glacial Maximum: New Radiocarbon Dates From Bluefish Caves, Canada," said humans may have lived in the Bluefish Caves in Yukon, Canada, 24,000 years ago. They based their findings on a horse jaw bone with human marks,

However, none of these finds have pushed the period back as far as the Mexican cave artifacts have.

Camels DON'T Store Water in Their Humps

Camels store fat on their humps, which they use as fuel when traveling great distances with limited resources. According to Animal Planet, a camel's fat may replace nearly three weeks' worth of food.

The camel's red blood cells are responsible for the camel's ability to go a week without drinking water. Britannica said Camels, unlike other animals, have oval-shaped blood cells that are more flexible and can store enormous amounts of water.

RELATED ARTICLE: How Do Arabian Camels Travel 100 Miles of Desert and Endure Weeks Without Water?

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