RECORD: Darwin, C. R. [1854.12.05]. Hooker states that his grave difficulty is that if you multiply an anomalous species by 100 it will seem to be anomalous & if you divide normal species by 100 it will become anomalous. CUL-DAR205.9.389. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 10.2021. RN1

NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR205.9 contains notes on palaeontology and geology [regarding theory of evolution].

Letter from J. D. Hooker to Darwin dated 5 December [1854]. CUL-DAR205.9.388


[389]

Hooker states that his grave difficulty is that if you multiply an anomalous species by 100 it will seem to be anomalous & if you divide normal species by 100 it will become anomalous I quite agree to latter & it proves thus that I am trying. Now I dispute the former proposition: if ornithorhynchus was made into a very large genus (according to analogy it cd not be multiplied by 100) & Echidna into another, they wd hardly be a whit less anomalous than now. But if you made many genera round about then, giving them either few or many species then they wd be not anomalous so marsupials can hardly be considered anomalous not if Didelphy existed alone, whether there was one or on at least just some dozen species, it wd be vastly anomalous. Earwig with species at one world is very anomalous – Sagitta most anomalous, yet I believe in at least a dozen species; if another 12 discovered in Pacific it wd remain equally anomalous. This begs the case it becomes a very fair subject

[389v]

of investigation whether the species is anomalous groups, as far as may, taking nearest & smallest groups, ie genera (as standard). It might by my theory be expected that they wd be few: possibly with exception.

N. B. I can make one great discussion about extinction in relation to individual species rarity preventing extinction.

(law of wide range & long duration in time) different rates of change, different classes – on relation to aberrant or anomalous genera.

If organisms disappear slowly there is some slight probability that they wd appear slowly & they do appear slowly.


Return to homepage

Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

File last updated 7 December, 2022