Theria by Ciro Santilli 37 Updated 2025-07-16
Every mammal except the weird monotremes, i.e. marsupials and the placentalia.
The name is completely random, "wild beast". Are platypuses not "wild beasts"? They have a freaking poison!!
Marsupial by Ciro Santilli 37 Updated 2025-07-16
They split up from the rest of the mammals after the monotremes.
Every other mammal has a placenta.
This baby in pouch thing just feels like a pre-placenta stage.
Bat by Ciro Santilli 37 Updated 2025-07-16
As of 2020, account for about 20% of the known mammal species!!! www.sciencefocus.com/nature/why-are-there-so-many-species-of-bat/ mentions some reasons:
  • they can fly, so they can move out further
  • their eating habits are highly specialized
Rat by Ciro Santilli 37 Updated 2025-07-16
Since rat and mouse are not scientifically specific names, we'll just use them interchangeably.
When one specific species is implied, we will mean Mus musculus by default.
Human by Ciro Santilli 37 Updated 2025-07-16
wget ftp://ftp.ncbi.nlm.nih.gov/refseq/H_sapiens/annotation/GRCh38_latest/refseq_identifiers/GRCh38_latest_genomic.fna.gz
gunzip --keep GRCh38_latest_genomic.fna.gz
Early human migrations by Ciro Santilli 37 Updated 2025-07-16
Video 1.
When We Took Over the World by PBS Eons (2019)
Source.
Human loss of fur by Ciro Santilli 37 Updated 2025-07-16
Video 1.
How Humans Lost Their Fur by PBS Eons (2020)
Source. Says it is linked to bipedalism to help hunting in hot weather. But could only happen fully after the invention of fire, otherwise you'd be too cold at night.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact