Humans kill a lot of sharks. Like, A LOT OF SHARKS. More than three every second to be exact. If we keep it up, several shark species will be extinct within the next few decades.
What would happen in a world without sharks?
That’s the question posed in this week’s episode of It’s Okay To Be Smart. From ecosystems to food chains to depressing death tallies to how much a shark is worth in $$$, there’s plenty of brain chum to watch and share with your fellow shark lovers.
Because lawyers, we’re calling it “Several Consecutive Calendar Days Dedicated to Predatory Cartilaginous Fishes" instead of… well, you know. And unlike certain cable TV channels, our videos are non-fearmongering, unsensationalized, and dedicated to celebrating and protecting sharks , not turning them into bloodthirsty monsters. This should go without saying, but all of the S.C.C.D.D.P.C.F. videos are 100% true, factual and not made up in the least bit, unlike some other shark-related programming.
Check out the full playlist of shark science videos from your favorite channels here, or you can watch it embedded below:
Hey everyone! I’m on my last day of vacation, but just wanted to let everyone know It’s Okay To Be Smart is teaming up with a few of your other favorite science YouTubers next week (like this one) to bring you something special that is related to several consecutive calendar days devoted to predatory cartilaginous fishes.
Except, you know, with science.
NEW VIDEO! Meet the oldest living things in the world…
I hope this video changes how you view a “lifetime”. Every organism you’re about to meet represents a single individual that has been alive for more than 2,000 years. Some of them have been around since before human society even existed.
This week, with the help of artist and photographer Rachel Sussman (whose photographs are collected in the amazing book The Oldest Living Things In The World), I explore some of Earth’s senior citizens.
A 5,000 year-old pine tree. An 80,000 year-old grove of aspens. A 100,000 year-old meadow of sea grass. Even 500,000 year-old, continuously-living bacteria… how did they get so old? Why do they live so long? Can these survivors survive us? And what others might be out there?
Dip your toe into deep time, and think about this: Is every moment a lifetime? Or Is every lifetime just a moment?
Watch the video below, and if you enjoy, please share and subscribe:
EXCERPTS >|< Life History of a Mosquito (1928)
| Hosted at: Internet Archive
A series of Animated GIFs excerpted from Life History of a Mosquito, a video showing life cycle of Aedes Aegypti: microphotography of eggs; larva, pupa and then adult mosquito emerging; female and male breeding. Made in 1928 by Kodak Research Laboratories, in co-operation with the Dept. of Bacteriology of the Medical School, University of Rochester.
We invite you to watch the full video HERE
BONUS scary skeeter stuff: Have you ever wondered what it looks like from inside your flesh as a female mosquito’s mouthparts are searching for blood slurps? There’s a video for that.
DOUBLE BONUS scary skeeter stuff: Yesterday I was looking up facts about malaria and mosquito-borne illnesses are responsible for more than 40 million lost years of life EVERY YEAR.
#7: Chernobyl Joe
We set a record for “turning Joe strange colors and setting him on fire” in this week’s OKTBS video.
Normal skin tones and sleeves will return next week!
The spotted handfish (Brachionichthys hirsutus), an amazing creature that walks the ocean floor, is a rare Australian fish from the family Brachionichthyidae. It is classified as Critically Endangered on the IUCN Red List 2002. is the first Australian marine species to be threatened with extinction.
The greatest threats to the handfish appear to be siltation and invasive species. The Derwent Estuary where the fish lives is highly urbanised and industrialised, and a range of marine pests have been introduced through shipping. One key pest is the Northern Pacific Seastar (Asterias amurensis), a particularly large and voracious predator that is now abundant in the estuary. Studies by CSIRO show that the seastars eat the stalked ascidians that the handfish use to attach their eggs.
- video CSIROpublishing
Like I always say, a fish with a hand is better than two in the bush
A gif representing nuclear fusion and how it creates energy.
For those who don’t understand the GIF. It illustrates the Deuterium-Tritium fusion; a deuterium and tritium combine to form a helium-4. Most of the energy released is in the form of the high-energy neutron.
Nuclear fusion has the potential to generate power without the radioactive waste of nuclear fission (energy from splitting heavy atoms into smaller atoms), but that depends on which atoms you decide to fuse. Hydrogen has three naturally occurring isotopes, sometimes denoted ¹H, ²H, and ³H. Deuterium (²H) - Tritium (³H) fusion (pictured above) appears to be the best and most effective way to produce energy. Atoms that have the same number of protons, but different numbers of neutrons are called isotopes (adding a proton makes a new element, but adding a neutron makes an isotope of the same atom).
The three most stable isotopes of hydrogen: protium (no neutrons, just one proton, hence the name), deuterium (deuterium comes from the Greek word deuteros, which means “second”, this is in reference two the two particles, a proton and a neutron), and tritium (the name of this comes from the Greek word “tritos” meaning “third”, because guess what, it contains one proton and two neutrons). Here’s a diagram
Deuterium is abundant, it can be extracted from seawater, but tritium is a radioactive isotope and must be either derived(bred) from lithium or obtained in the operation of the deuterium cycle. Tritium is also produced naturally in the upper atmosphere when cosmic rays strike nitrogen molecules in the air, but that’s extremely rare. It’s also a by product in reactors producing electricity (Fukushima Daiichi Nuclear Power Plant). Tritium is a low energy beta emitter (unable to penetrate the outer dead layer of human skin), it has a relatively long half life and short biological half life. It is not dangerous externally, however emissions from inhaled or ingested beta particle emitters pose a significant health risk.
During fusion (energy from combining light elements to form heavier ones), two atomic nuclei of the hydrogen isotopes deuterium and tritium must be brought so close together that they fuse in spite of the strongly repulsive electrostatic forces between the positively charged nuclei. So, in order to accomplish nuclear fusion, the two nuclei must first overcome the electric repulsion (coulomb barrier ) to get close enough for the attractive nuclear strong force (force that binds protons and neutrons together in atomic nuclei) to take over to fuse the particles. The D-T reaction is the easiest to bring about, it has the lowest energy requirement compared to energy release. The reaction products are helium-4 (the helium isotope) – also called the alpha particle, which carries 1/5 (3.5 MeV) of the total fusion energy in the form of kinetic energy, and a neutron, which carries 4/5 (14.1 MeV). Don’t be alarmed by the alpha particle, the particles are not dangerous in themselves, it is only because of the high speeds at which they are ejected from the nuclei that make them dangerous, but unlike beta or gamma radiation, they are stopped by a piece of paper.
Some fundamentals of fusion.