AI Use Note: Main body text entirely human written. Claude (Opus 4.8) helped develop models of animal life histories in the appendix.

Cross-posted from Good Structures.

• Animal advocates sometimes make claims like “there are X of this animal, and Y>X of this animal, so Y might be a better target to focus on.”
  • For example, you could imagine someone making a claim like “there are 20 quadrillion ants, so they are a higher priority to work on than Pacific salmon (wild population size: ~500M), even accounting for moral weight and welfare range.”
  • Some arguments for working on farmed over companion, or wild over farmed animals, take this shape – where population size serves as a rough heuristic for prioritization.
• These claims frequently rely on abundance estimates produced by conservation- and evolution-focused scientists, who primarily focus on estimating the“stable adult population,” since reproductively active individuals are what's relevant to evolution and species continuity.
• We show that:
  • Using stable adult populations systematically underestimates the number of animals who will live over a specific period. Using stable adult populations systematically underestimates morally relevant experiences of some small and heavily r-selected animals.
• Given this, we argue that:
  • [...]

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Outline:

(00:27) Executive Summary

(03:09) Introduction

(07:22) What do abundance estimates actually count?

(09:11) Callaghan et al. 2021 -- Global Bird Abundance

(12:52) Comparing five example groups of animals

(16:44) Implications for impact estimates

(19:11) Takeaways

(21:48) Appendix A: Methodology for animal throughput estimates

(22:37) Common framework

(23:43) Wild pacific salmon

(24:15) Passeriform birds

(24:41) Grasshoppers

(25:08) Ants

(25:37) Aphids (asexual summer phase)

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First published:

Source:

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Narrated by TYPE III AUDIO.