Кости крыла стрижа. Источники - <a rel="nofollow" class="external text" href="https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2013.0580">Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes)</a> (очертания крыла Hirundapus caudacutus) и <a rel="nofollow" class="external autonumber" href="http://www.reptileevolution.com/tyto.htm">[1]</a> детализация косточек Apus apus.
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<span class="int-own-work" lang="en">Own work</span>