Phylum Chaetognatha: Arrow Worms

The organisms in phylum Chaetognatha are known as arrow-worms, or bristle-jaws. They have a very interesting anatomy and eating habits. Their phylogeny is tricky and still in flux, so let's learn about what we know right now!
Script by Ryan Helcoski and Dr. Carsten H G Müller: www.researchgate.net/profile/...
Additional collaboration by Dr. Yvan Perez: www.researchgate.net/profile/...
Handbook of Zoology: www.degruyter.com/database/zo...
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[@n0limits]

Hello Professor, can you please start a topology series? Thanks a lot

[@Ethan-qe1xs]

Dave thanks so much! These videos are so helpful and both effectively and efficiently teach me material I have tests on at school. I have recommended this channel to a multitude of people, keep going

[@idkjustleavemebeplease]

I don't know how I ended up here, watching an informational video about a hermaphrodite worm that is rather phallic in design, yet here I am.

[@40g33k]

Thanks, more stuff to fuel my nightmares....

[@user-rs6by2mr8k]

THANK YOU VERY MUCH!!!!!!!!!!!! Thanks to you, I finally understood who they were, and they turned out to be incredibly interesting animals. I want to shake your hand, you have served the material perfectly

[@sciencenerd7639]

I love this series. Thanks, keep up the good work!

[@RUIGARAGE]

Obrigado

[@nicco-sixty]

Please have differential equations soon

[@juliehenderson4398]

Hello Professor Dave! Love your videos, and they’re so helpful!! Could you please make some calculus 2 videos? Thank you so much!!

[@ProfessorDaveExplains]

I did! Check my calculus playlist!

[@juliehenderson4398]

@@ProfessorDaveExplains Thank you so much!!

[@errolkatz2218]

Dave, when I was in 8th grade middle school biology (late 80's, early 90's) I am pretty sure we did an experiment with this species (had to have been the fresh water variety as I was in Indiana) but I specifically remember splitting their head (under a microscope) and they would grow new heads? Please correct me if I'm wrong, but pretty sure they were "arrow" worms...8th grade biology was also an earthworm, sheep eye, owl pellet, frog and the grand finale an unborn baby pig. I loved the Owl pellet, we had to figure out what it ate.

[@ryanhelcoski6894]

You're thinking of planarians, specifically the free-living flatworms that can regrow heads: kzbin.info/www/bejne/h5-5hZ6DbZWCj6M

[@sarahelhanouni9239]

could it have been a planarian what u dissected? they kinda look like they have arrow heads and are well studied for their rejuvenating capabilities.

[@jameshall1300]

Yeah, planarians are famous for being able to be cut into over a hundred pieces and every piece is able to regenerate into a whole, living worm again.

[@kane2875]

yesssss arrow worm video

[@billyr2904]

According to wikipedia, chaetognatha is a gnathiferan phylum.

[@petrfedor1851]

Many groups organisms appear in Cambrian explosion but none of them manage to put themself into ecological niche with such an ease to lurk around almost unchanfed ofter more than half billion years.

[@masimunukka2595]

cool

[@magicsasafras3414]

Mmm. Terrifying.

[@harrybeaumont0621]

Has to be how the dinosaurs evolved , micro organisms getting bigger over 2.01 billion years since the oxidation event

[@davidwatson2399]

👍😎

[@-JA-]

👏👍

[@Commander_Appo]

I saw the thumbnail while scrolling and I thought that was a, er, male rod?

[@hollowknightenjoyer]

What

[@donchristie420]

Dave, what time was I to be over for supper- please answer your shoe phone

[@revan552]

Professor, I know the subject is better suited to the psychology courses you put out a few years back; but I'm curious. Is "subliminal message and reprogramming the mind" scientific, or is it pseudo-scientifuc nonsense? It's a huge thing for the Quantum Mystic charlatans, and New-Age quacks, but I'd love to watch a video regarding the actual science and efficacy regarding intentional subliminal messaging (such as KZbin videos and affirmations etc) in mental health, mindset, and behavioral modification. Is there any validity to it, or is it just more empty nonsense peddled by quacks? Thanks! Love your work, you helped get me free of the religious cult I was raised in!

[@christiandehlinger]

Amazing God!

[@adams9791]

This debunk video sucks. 🤣🤣🤣 I'm just kidding. Don't blame you for taking a step away from the insanity of the Flerfs...

[@The_ever_preset_Bee_Eater]

The Waffle House has found its new host