MR. MARTIN has directed attention in NATURE of July 5, p. 12, to the fact that birds may carry shellfish to heights considerably above sea-level, and I remember as a student being warned against a too ready assumption of elevation of the land relatively to the sea founded on the occurrence of remains of mollusca above high-water mark. But the operations of birds in the past history of the world were probably far more extensive. Their efficiency in the distribution of seeds and minute organisms over seas is now generally acknowledged, and of course we are indebted to birds for valuable deposits of guano.

Affiliations

1. Imperial College of Science and Technology, S. Kensington, S.W.7, July 7.

   • J. W. EVANS

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Publication history

DOI

https://doi.org/10.1038/114089b0

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