\[ **BT: [[life]]** ]
---
# the biosphere
The biosphere is the worldwide sum of all [[#ecosystems]].[^1]
The biosphere is the apex of biological organisation (with the smallest being [[matter and energy#atoms|atoms]] and the largest the biosphere).[^2]
## ecosystems
An ecosystem is a collection of integrated communities and their environment.
## biological populations and communities
### biological populations
#### deme
Pronunciation: homophone with *deem*.[^3]
[[A deme is a distinct population or territory of animals, all of the same species, which share a common gene pool (i.e. they interbreed).]][^4]
### biotic interactions
[[Without fungi, no life on land would exist.]][^2]
## hazards of life in the biosphere
### terrestrial ecosystems
#### the land environment
##### specialised biomes
###### polar biomes
[[Polar T3 Syndrome, found in polar explorers, is caused by a drop in thyroid hormone T3.]][^5]
- see also:
- [[human beings#the thyroid|thyroid disorders]]
- [[Earth#the polar environment|the polar environment]]
## bio-geographic distribution of organisms: ecosystems
### terrestrial ecosystems
#### the land environment
##### major terrestrial environments
e.g., the tundra, the coniferous forest, the middle-latitude forest, the tropical rain forest, the grassland and savanna, the scrublands, the desert
###### forests
![[Sheldrake, Entangled Life, 2021#^b6348f]]
[^6]
###### polar environment
- see also: [[Earth#polar environment]]
## the place of humans in the biosphere: human ecology; human biohistory; etc
- see: [[human ecology]]
[^1]: Tristram D. Wyatt, ‘[[Wyatt, ‘Pheromones’, 2017|Pheromones]]’, *Current Biology*, vol. 27, no. 15 (2017), R740, <https://doi.org/10.1016/j.cub.2017.06.039>.
[^2]: Merlin Sheldrake, *[[Sheldrake, Entangled Life, 2021|Entangled Life: How Fungi Make Our Worlds, Change Our Minds, and Shape Our Futures]]* (Vintage, 2021), p. 2.
[^3]: ‘Deme’, Wiktionary, last edited 30 July 2025, 14:42, https://en.wiktionary.org/wiki/deme.
[^4]: ‘Deme’, Wiktionary, last edited 30 July 2025, 14:42, https://en.wiktionary.org/wiki/deme; ‘What Is a Deme and Its Role in Evolution?’, *Biology Insights*, 26 July 2025, https://biologyinsights.com/what-is-a-deme-and-its-role-in-evolution/.
[^5]: Translator’s note in 壶鱼辣椒 \[Pot Fish Chili], *[[Pot Fish Chili, I Became a God in a Horror Game, 2020|I Became a God in a Horror Game]]*, trans. 19 Dollar Company (19 Dollar Company, 2025), chapter 252, <https://19dollarcompany.wordpress.com/2023/09/22/ghg-chp-252/>.
[^6]: Merlin Sheldrake, *[[Sheldrake, Entangled Life, 2021|Entangled Life: How Fungi Make Our Worlds, Change Our Minds, and Shape Our Futures]]* (Vintage, 2021), p. 13.