Wonderful to hear this recording! I want to add a reference for those interested in Gordon's insight that we have extra-keen hearing in the same range as birdsong, and why that might be. Jon Young (his book is What the Robin Knows) has studied birdsong and what its roles would have been for people such as hunter/gatherers. It's a wonderful book about sitting in the quiet, listening to what birds are telling us about their lives as well as the environment around them.
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