Earlier this month we covered elephants, the largest land animal in the world. Today we’ll cover another large land animal: hippopotamuses! Here’s some fun facts about hippos:

🦛 Hippos are the third largest land animal in the world. Male hippos can weigh up to 6,000 pounds, equivalent to 2-3 small cars! So, not surprisingly, they eat a lot - hippos can eat up to 100 pounds of plants and vegetation a day!

🦛 Hippos have a unique “sweat” - an oily red substance that acts as a natural sunblock and moisturizer. It also has antibacterial properties to keep the hippos healthy! However, despite this natural sunblock, because hippos don’t have hair, they still spend most of their day in water to stay cool and protect their skin from the sun.

🦛 Despite their size, don’t try to outrun a hippo! On land, they can run up to 19 mph for short distances!

🦛 Hippos have a unique jaw structure, powered by very strong muscles, which enable it to open its mouth almost a full 180-degrees! This gives them a very powerful (and lethal!) bite! Which leads us to…

🦛 Hippos are the most dangerous animal in Africa! They are highly territorial and get very aggressive if you get too close. Here's the most dangerous animals in Africa (not including mosquitos, because they're insects):

Don’t be fooled by outward appearances! 👀

Did you know that clouds can weigh up to 1 million pounds?

Clouds are actually quite heavy! Different types of clouds have different densities and volumes. However, for cumulus clouds which have a density of around 0.5 grams (0.001 pounds) per cubic meter, that means a typical cloud can weigh up to 1 million pounds!

While that seems quite heavy, they're still able to stay afloat because of raising air currents and because clouds are less dense than the air beneath them.

But even though they’re so big, clouds can also be quite fast! While it depends on the cloud type and wind conditions, some high-level clouds can reach 100 mph!

Do goldfish really forget after 3 seconds?

One common belief is that goldfish forget everything after 3 seconds. However, this isn’t true - goldfish have excellent memories! They can recognize their owners and remember things for months and even years!

In fact, they’re capable of performing complex tasks including recognizing shapes, colors, and navigating mazes. They can even be trained to perform tricks, such as playing fetch, pushing a ball, and even jumping through a ring!

So the next time someone says your memory is as short as a goldfish’s, that’s quite the compliment! 😂

DNA (deoxyribonucleic acid) is the genetic instruction manual for life. Nearly every cell of every living organism uses DNA as its blueprint, telling it how to grow and function.

In 2012, scientists Jennifer Doudna, Emmanuelle Charpentier, and Feng Zheng demonstrated that a new technology called CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) could be used to change a cell’s DNA. This means that scientists could now edit a cell’s DNA to selectively turn genes on or off, and in doing so, potentially completely reprogram a cell’s function. While scientists were able to do this before using other techniques, CRISPR made this work much, much faster, cheaper, and accessible for almost every lab to use. CRISPR has been called one of the most significant discoveries in the history of biology, and it has completely transformed the field, ushering in the era of genome editing.

CRISPR uses a specialized protein called Cas9, which is actually part of bacteria’s natural immune system. Doudna, Charpentier, and Zheng showed that scientists can introduce Cas9 into human cells, along with a guide to direct it to specific locations in the cell’s DNA. The Cas9 then cuts the DNA, which causes the cell’s repair mechanisms to kick in. Scientists can use this to cut a specific gene’s DNA to disable it, to correct an existing mutation, or even to introduce new genetic material.

Using CRISPR, scientists have made pretty remarkable progress in tackling various diseases caused by genetic mutations, including being able to completely cure Sickle Cell Anemia!

A light bulb classic: 💡 You are in a room with three switches that control three light bulbs in another room. You can only enter the other room once. How do you determine which switch controls which bulb?

(Answer is at the end)

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