Photosynthesis by Ciro Santilli 37 Updated 2025-07-16
It is quite cool that photosynthesis works just like cellular respiration by producing a proton potential through chemiosmosis.
Phylogenetic tree by Ciro Santilli 37 Updated 2025-07-16
It is important to note that due to horizontal gene transfer, the early days of life, and still bacteria to this day due to bacterial conjugation, are actually a graph and not a tree, see also: Figure "Graph of life".
Definitely have a look at: coral of life representations.
Cladogram by Ciro Santilli 37 Updated 2025-07-16
TODO vs Phylogenetic tree? www.visiblebody.com/blog/phylogenetic-trees-cladograms-and-how-to-read-them:
Cladograms and phylogenetic trees are functionally very similar, but they show different things. Cladograms do not indicate time or the amount of difference between groups, whereas phylogenetic trees often indicate time spans between branching points.
Basal (phylogenetics) by Ciro Santilli 37 Updated 2025-07-16
When a characteristic is basal, it basically means the opposite of it being polyphyletic.
E.g. monotremes laying eggs did not evolve separately after function loss, it comes directly from reptiles.
Crown group by Ciro Santilli 37 Updated 2025-07-16
Kind of the opposite of a basal group.
Taxonomic rank by Ciro Santilli 37 Updated 2025-07-16
Naming taxonomic ranks like genus, domain, etc. is a fucking waste of time, only useful before we developed molecular biology.
All that matters is the tree of clades with examples of species in each clade, and common characteristics shared by the clade.
And with molecular biology, we can build those trees incredibly well for extant species. When extinct species are involved however, things get more complicated.

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 5. . 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.
  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