@article {58406,
	title = {A new look at universals and specificities in the songs of humpback whales.},
	journal = {Journal of Comparative Psychology},
	volume = {135},
	year = {2021},
	month = {Jan-02-2021},
	pages = {25 - 27},
	abstract = {<p>In this issue\&rsquo;s featured article, Mercado and Perazio (2021) describe songs of humpback whales using acoustic qualities, in part to determine the degree of similarity in songs across time and space that have not been revealed by information-theoretic analyses. They are particularly interested in evaluating alternative explanations of song variations in humpback whales. They argue that if humpback whales\&rsquo; songs \&ldquo;are . . . transmitted through acoustic contact followed by imitation\&rdquo; (p. 29) then (a) songs of populations not in acoustic contact should diverge, (b) songs of the same population should diverge increasingly over time, and (c) song forms separated by multiple decades either within or across populations should be dissimilar. Alternatively, acoustic similarities in song structure across populations and/or across decades in the same population would challenge the hypothesis that socially mediated learning is the primary driver of variation in the structure of humpback whales\&rsquo; songs over time. If that is the case, then identifying universal properties of song composition is important to move the field forward. Broadening the analytical tool kit can help in this effort.</p>
},
	issn = {0735-7036},
	doi = {10.1037/com0000270},
	url = {http://doi.apa.org/getdoi.cfm?doi=10.1037/com0000270},
	author = {Fragaszy, Dorothy Munkenbeck}
}
@article {58404,
	title = {Similarities in composition and transformations of songs by humpback whales (Megaptera novaeangliae) over time and space.},
	journal = {Journal of Comparative Psychology},
	volume = {135},
	year = {2021},
	month = {Jan-02-2021},
	pages = {28 - 50},
	abstract = {<p>The complex songs produced by humpback whales have been cited as evidence of prodigious memory, innovativeness, sophisticated auditory scene analysis, vocal imitation, and even culture. Researchers believe humpbacks learn their songs culturally because songs appear to change rapidly, consistently, and irreversibly across whales within a population. Here, we present evidence of similarities in song structure both across populations and decades that strongly challenge claims that social learning is the main driver of variations in humpback whale songs over time. Groups of humpback whales that were not in acoustic contact (recorded in Puerto Rico in 1970, Hawaii in 2012, and Colombia in 2013\&ndash;2019) produced songs in acoustically comparable cycles, suggesting that progression through sound patterns within and across songs is not simply determined by vocal imitation of innovative patterns, but may instead be controlled by production templates that prescribe how singers construct and transform songs over time. Identifying universal constraints on song production is critical to evaluating the role of vocal imitation and cultural transmission in the progressive changes that humpback whales make to their songs and for evaluating the functional relevance of such changes. The current findings illustrate how information theoretic analyses of vocal sequences can potentially obscure key acoustic qualities of signals that may be critical to understanding how vocalizers produce, perceive, and use those sequences.</p>
},
	issn = {0735-7036},
	doi = {10.1037/com0000268},
	url = {http://doi.apa.org/getdoi.cfm?doi=10.1037/com0000268},
	author = {Mercado, Eduardo and Perazio, Christina E.}
}
