\[ **BT: [[animals]]** ]
---
# chordates
## classification of chordates
| CHORDATA | |
| --------------------------- | ------------------------------------------ |
| [[#Vertebrata (Subphylum)]] | vertebrates |
| Tunicata | tunicates (sea squirts, salps, larvaceans) |
| Celphalocordata | lancelets |
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### Vertebrata (Subphylum)
#### classification of vertebrates
| VERTEBRATE GROUPS | | | Class | Notes |
| ----------------------------------------------------------- | ------- | --------- | ----------------------------------------------- | ------------------------------------------------ |
| Anamniote \[no amniotic membrane = must reproduce in water] | Jawless | “Fish” | Myxini | hagfish |
| Anamniote | Jawless | “Fish” | Hyperoartia | lampreys |
| Anamniote | Jawed | “Fish” | Chondrichthyes | cartilaginous fishes (e.g. sharks, rays, skates) |
| Anamniote | Jawed | “Fish” | [[ray-finned fish#Actinopterygii (Class)\|Actinopterygii]] | ray-finned fish |
| Anamniote | Jawed | “Fish” | “Sarcopterygii” | lobe-finned fish |
| Anamniote | Jawed | Tetrapods | [[#Amphibia (Class)]] | amphibians |
| Amniote \[have amniotic membrane = can reproduce in land] | Jawed | Tetrapods | “[[reptiles\|Reptilia]]” | reptiles |
| Amniote | Jawed | Tetrapods | [[mammals\|Mammalia]] | mammals |
| Amniote | Jawed | Tetrapods | [[birds\|Aves]] | birds |
| Amniote | Jawed | Tetrapods | | |
[^1]
- **NT:**
- [[birds]]
- fish
- [[ray-finned fish]]
- [[mammals]]
- [[reptiles]]
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#### Amphibia (Class)
[[There is a fungal disease, which infects amphibians, has been spread internationally via humans; it has already driven at least ninety species to extinction and threatens hundreds more.]][^2]
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#### endothermic vertebrates
\[warm-blooded vertebrates]
##### strategies
###### torpor
- see: [[torpor]]
[^1]: ‘Vertebrate’, Wikipedia, last edited 24 December 2025, 01:24 (UTC), <https://en.wikipedia.org/wiki/Vertebrate>.
[^2]: Merlin Sheldrake, *[[Sheldrake, Entangled Life, 2021|Entangled Life: How Fungi Make Our Worlds, Change Our Minds, and Shape Our Futures]]* (Vintage, 2021), p. 9.