Hank Green from the past! Well, I suppose it's always Hank Green from the past but this time it's not a technicality, it's actually Hank from 9 years ago!

I'll explain ball lighting being seen on submarines. On my first deployment on a submarine, I once went 5 days without sleep. I absolutely saw things that weren't there

That section on methane craters was fascinating. It’s a reminder of how Earth’s chemistry and geology are still writing the story in real time.

Young Hank was quite the jumpscare. His elocution style has changed so much.

As someone who lives near the equator it is nice, not worrying about seasons or varying day and night times, having fruits year round.

I'm a KREEP
I'm a moon rock
What the hell am I doing here?
Scientists don't yet....

Remember, tectonic plates weren't an accepted reality until the 1960's!

A compilation of compilations! Reminds me of how much I miss some of the presenters who are no longer making SciShow video. Thanks to everyone at SciShow

49:48 I think it’s important that people realize that extinction events occur over a massively long period of time, compared to human life spans. It’s not just like boop and it’s all done. But that also can happen.

I've heard the fine-tuning problem compared to a puddle waking up in a pothole and marvelling at how the pothole is so perfectly formed for the puddle to sit inside it. Of course we're going to measure fundamental constants that are favorable to life developing, because if they weren't, we wouldn't be around to measure them.

My house is also on a lake that freezes in winter.  On really warm winter days the lake will do a sudden crack with a SONIC BOOM.  I had one lake sonic boom knock me down as a teenager.

Omg I thought this would be average length and thus maybe 5-10, so let me convey my thoughts as soon as she said 60 and saw 2 hrs - OHHHH YEAHHH SCISHOW REALLY IS THE BEST THANK YOUUU!!!

The boom in multicellular life segment is really about animals specifically.  Something that is interesting is that if you look at molecular clocks, you see that the last common ancestor between all animals and choanoflagellates (our closest unicellular relatives) was about 800 million years ago.  The last common ancestor of all living animals was somewhere around 600 million years ago.  In the intervening period, at least 7 whole genome duplications, and three major signalling families that are all crucial to animal embryonic development (Wnt, Sonic Hedgehog, and TGF-beta/BMP) all emerged specifically in the animal lineage.  It's hard for biological systems to make new genes, and it's even harder to make new signaling pathways because you need multiple genes to start working together in new ways.  It's also a great chicken and egg question because if the organisms were not yet multicellular, where was the selective pressure to assemble these pathways, but if they were already multicellular, how did they achieve it without the pathways?  Something crazy was happening in the animal lineage between 800 and 600 million years ago, and the fossil record has basically nothing to say about it - both the Ediacaran and cambrian explosions happened shortly afterwards.  During most of that period the atmosphere had relatively low oxygen and the earth froze a bunch of times.  It also comes right after the so-called "boring billion".  My best guess is that the animal ancestors during this period were experimenting with multicellularity on a tiny scale - but such a fascinating period of life's history and so shrouded in mystery.

We’re missing gravity in the Indian Ocean because that’s where the Celestial emerged from. Gees…doesn’t anyone watch the Marvel documentary’s?

it would be neat to revisit the "biggest mysteries" compilations in a video that talks about latest breakthroughs (or full answers) to the mysteries. By themselves they probably don't warrant their own video but you could definitely string about 5-10 of them together into one decent length episode

Those circle hills were me. I needed cool stuff for my Tonka trucks to drive on.

I miss when Olivia hosted episodes of the show!! She was so great!

This might be my favorite compilation yet - all things earthy!  It's also really lovely seeing bygone scishow host friends 🥰  Hi friends!!  A treat to have both Olivia and Savannah in one video 😊

Something oddly comforting about a compilation like this. The fact that some of the most basic questions, like why we even need to sleep, are still wide open keeps science exciting. Great watch.

I binged this WHOLE compilation in one go! Love this damn show.