Why Aren't There Giant Insects?

Hank and physiologist Jon Harrison discuss the question of insect size and major theories that attempt to explain why there is a limit to how large insects can get with current conditions on Earth. Like SciShow @ http://www.facebook.com/scishow Follow SciShow @ http://www.twitter.com/scishow References http://www.prehistoric-wildlife.com/species/m/meganeura.html http://www.telegraph.co.uk/earth/wildlife/8930070/Worlds-biggest-insect-...

Comments

1. Why was everything larger then? It was not just bugs was it? There were quite a lot of species on land that were larger than their modern relatives. Bigger Dinosaurs, bigger reptiles, bigger snakes, bigger mammals, it seems like they all had some really big species in the past that no longer exist. I wonder if Dinosaurs would even be able to exist in our current earth, or if there was not some other factor in the past that made their size possible.
2. i would rather bugs be huge then small because you would notice a bug the size of a dog or cat the small ones go unnoticed
3. a spider isnt a insect
4. the real reason bugs arent big is because satan is going easy on us
5. What if I want a Yanmega!?
6. How about we experiment a Spider Goliath to make them more bigger?
7. what about the goliath bird eater?
8. When I was little I thought the world was encased in a bubble, and giant wasps would get into the bubble and take me away and sting me to death. Still gives me goosebumps.
9. I know that this video is 5 years old . But there are a differents between hypothesis and theories.
10. Spiders aren't insects by the way, you should have called this video Giant Arthopods or something.
11. well why dont they make a room or something with a higher oxygen content and put some bugs in it, or poke around with their DNA and see if thier a trait that make them larger.
12. what about the exoskeleton shedding theory? since the only way the exoskeleton can grow is by growing a new one and shedding the older. as the insect gets bigger it'll also need more time to develop a new exoskeleton which means it'll have to spend more time unprotected during this time.
13. Maybe it's something similar to why Mammals aren't as big? Lot less food, plus less oxygen, could be it, since most eat plants, and for those that eat other Bugs, smaller the food, the smaller they'd get from not having enough food to sustain themselves
14. Has nobody tried breeding insects (or other arthropods) in oxygen-rich environments? I get the argument about exoskeleton mass, but what if they were bred in low gravity, say, on the moon. Might be interesting to see what would happen.
15. NO!!!
16. ah my favorite host,
17. Just imagine, there is a version of reality here earth has higher oxygen, allowing insects and arachnids to be bigger, and humans decided to domesticate them instead of cats and dogs. So, giant police spiders are a thing, in at least one version of reality. If you subscribe to the multiple worlds hypothesis that is.
18. So why not breed insects in a more oxygen rich enviroment and see if they grow larger?
19. 0:00 I try not to.
20. Has any studies been done to grow generations of insects in a oxygen rich environment. Insects reproduce and mature quickly and dont require a lot of space. Why not make a special air tight container and keep the oxygen levels at a constant high level.