The statocyst is a balance sensory receptor present in some aquatic invertebrates, including bivalves, cnidarians, ctenophorans, echinoderms, cephalopods, and crustaceans. A similar structure is also found in Xenoturbella. The statocyst consists of a sac-like structure containing a mineralised mass (statolith) and numerous innervated sensory hairs (setae). The statolith's inertia causes it to push against the setae when the animal accelerates. Deflection of setae by the statolith in response to gravity activates neurons, providing feedback to the animal on change in orientation and allowing balance to be maintained. In other words, the statolith shifts as the animal moves. Any movement large enough to throw the organism off balance causes the statolith to brush against tiny bristles which in turn send a message to the brain to correct its balance. It may have been present in the common ancestor of cnidarians and bilaterians. (Wikipedia).
What is a (mathematical) model?
"Model" is a vague term that means different things in different contexts. Here I clear it all up in the context of statistics! For a complete index of all the StatQuest videos, check out: https://statquest.org/video-index/ If you'd like to support StatQuest, please consider... Buying T
From playlist StatQuest
Hello, and welcome to StatQuest! StatQuest is about learning how to visualize and "see" how statistics work without getting too bogged down in the equations. Once you can get an image in your head of how statistics work, the equations make sense and come easy.
From playlist StatQuest
Quantiles and Percentiles, Clearly Explained!!!
Although there is a ton of conflicting information about quantiles and percentiles on the internet, this StatQuest filters out the noise and focuses and the most important things you need to know about these two summary statistics. For a complete index of all the StatQuest videos, check o
From playlist StatQuest
Four Ways Animals Know Which Direction Is Up
Visit https://brilliant.org/scishow/ to get started learning STEM for free, and the first 200 people will get 20% off their annual premium subscription. While many animals don't have the same gravity-sensing organs we do, they still manage to figure out which way is up! Hosted by: Rose B
From playlist Biology
More Standard Deviation and Variance
Further explanations and examples of standard deviation and variance
From playlist Unit 1: Descriptive Statistics
Phylum Xenacoelomorpha and an Introduction to Nephrozoa
Most of the animals we are familiar with are contained in Nephrozoa, as these are the triploblastic and bilaterally symmetrical animals. The phyla we've covered so far are not part of Nephrozoa, and we have one more to cover before we get there, Xenocoelomorpha. This contains worm-like tri
From playlist Zoology
p-values: What they are and how to interpret them
This StatQuest is all about interpreting p-values. You've seen them online or in publications, or heard about them, whispered in dark, rave filled dance clubs, but you've never understood what they were all about. This 'Quest is here to explain everything you wanted to know about how to in
From playlist StatQuest
The Aquatic Snails That Leave a Path of Destruction
Visit http://brilliant.org/microcosmos/ to get started learning STEM for free, and the first 200 people will get 20% off their annual premium subscription. It’s often said that one person’s trash is another person’s treasure. And surely there is no greater proof of that than the home of o
From playlist Season 6
Drawing and Interpreting Heatmaps
This StatQuest is about the heatmaps. We see these all the time, but there are lots of arbitrary decisions that go into drawing them. Here, I show you what those decisions are and how they affect the results. For a complete index of all the StatQuest videos, check out: https://statquest.
From playlist StatQuest
StatQuest: Logistic Regression
Logistic regression is a traditional statistics technique that is also very popular as a machine learning tool. In this StatQuest, I go over the main ideas so that you can understand what it is and how it is used. For a complete index of all the StatQuest videos, check out: https://statq
From playlist StatQuest
A Gentle Introduction to Machine Learning
Machine Learning is one of those things that is chock full of hype and confusion terminology. In this StatQuest, we cut through all of that to get at the most basic ideas that make a foundation for the whole thing. These ideas are simple and easy to understand. After watching this StatQues
From playlist StatQuest
Phylum Ctenophora: Comb Jellies
The next phylum we will cover is Ctenophora, home to the comb jellies, like the sea gooseberry and sea walnut. These are quite a bit different from true jellyfish of phylum Cnidaria. Let's see what these strange creatures are all about! Script by Ryan Helcoski Watch the whole Zoology pla
From playlist Zoology
Statistic vs Parameter & Population vs Sample
This stats video tutorial explains the difference between a statistic and a parameter. It also discusses the difference between the population and sample. It includes examples such as the sample mean, population mean, sample standard deviation, population standard deviation, sample propo
From playlist Statistics
Phylum Platyhelminthes Part 2: Free-Living Flatworms and the Problem With Turbellaria
With the basics regarding phylum Platyhelminthes covered, it's time to start digging into the clades within. Free-living flatworms were originally classified within the class Turbellaria. But more recently the clades needed to be rearranged, so instead this tutorial will focus on members o
From playlist Zoology
Machine Learning Fundamentals: Bias and Variance
Bias and Variance are two fundamental concepts for Machine Learning, and their intuition is just a little different from what you might have learned in your statistics class. Here I go through two examples that make these concepts super easy to understand. For a complete index of all the
From playlist StatQuest