541,000,000: The longest ago, in years, “that animals acquired some basic sound-making behaviors related to locomotion and predation”
200,000,000: The number of years later “before the buzzing of insects started to fill the air”
230,000,000: The number of years ago when “vertebrate animals evolved a wide range of vocal abilities”
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¹Footnotes: All items from scientificamerican.com.
Originally published in the January 17, 2022, edition of the This Week in Sound email newsletter (tinyletter.com/disquiet).