Avian cranial evolution + Scopsoides, new bird from Eocene of Germany + bird elongated tails genetic basis

[Ben Creisler]

Ben Creisler

bcre...@gmail.com

Recent avian papers:

Free pdf:

Andrew Knapp, Taylor West, Catherine M. Early & Ryan N. Felice (2025)
Avian cranial evolution is influenced by shape interactions between hard and soft tissue traits
Proceedings of the Royal Society B: Biological Sciences 292(2061): 20250848.
doi: https://doi.org/10.1098/rspb.2025.0848
https://royalsocietypublishing.org/rspb/article/292/2061/20250848/366140/Avian-cranial-evolution-is-influenced-by-shape?searchresult=1


Changes in the structure and relative size of the brain are thought to be key transformations in the evolution of birds, reflecting innovations and diversity of neurosensory and cognitive capabilities. These changes do not occur in isolation, being accompanied by many other derived morphological characteristics. In the avian head alone, these include the evolution of a toothless beak, an increase in relative eye size, and a reduction and restructuring of jaw muscles. Several developmental trade-offs have been proposed to explain the interrelationships among these traits, but how these developmental patterns translate into evolutionary correlations among cranial traits is poorly understood. Here, we use two-block partial least squares analyses and Ornstein–Uhlenbeck models of adaptive trait evolution to explore the phenotypic evolution of hard and soft cranial tissues and test hypotheses of correlated trait evolution. In pairwise analyses, we found that all traits are significantly correlated, and found support for a form of adaptive trait evolution across the whole head in which traits interact reciprocally via the neurocranium. Together, these results highlight the integrated nature of the avian head and reveal that the evolution of diverse phenotypes is a result of complex multiple interactions among hard and soft tissue traits.

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Scopsoides feisti gen. et sp. nov.

 
Gerald Mayr (2025)
A new genus and species of the Halcyornithidae (Aves) from the Eocene of Messel (Germany)
Neues Jahrbuch für Geologie und Paläontologie (advance online publication)
doi: 10.1127/njgpa/1295
https://www.schweizerbart.de/papers/njgpa/detail/prepub/107526/A_new_genus_and_species_of_the_Halcyornithidae_Ave

A new genus and species of the Halcyornithidae is reported from the Eocene fossil site Messel in Germany. Unlike most other halcyornithids, Scopsoides feisti gen. et sp. nov. has a short and stout tarsometatarsus without a plantarly open hypotarsal sulcus. With regard to these features, it agrees with the distinctly larger halcyornithid species Serudaptus pohli, but the insufficiently understood interrelationships of early Eocene zygodactyl birds impedes a straightforward assessment of the phylogenetic significance of these resemblances. The similar tarsometatarsus morphology of Scopsoides and Serudaptus may characterize a previously unrecognized halcyornithid subclade. However, the tarsometatarsus of the new species likewise shows similarities in its proportions to that of the phylogenetically more distant early Eocene taxon Avolatavis, so that the stoutness of the bone could well be plesiomorphic. The varying foot morphologies of halcyornithids indicate disparate locomotory characteristics or a different use of the feet in food manipulation or prey handling.

 
http://zoobank.org/urn:lsid:zoobank.org:pub:1C654F50-1A19-423A-AC88-283F8436ECFB

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Hui Wang, Yu Liu, Nan Lyu, Zhengwang Zhang, De Chen & Qiong Liu (2025)
The Genetic Basis of Elongated Tails in Birds: Evidence for Sexual Selection as a Driver of Convergent Evolution
Integrative Zoology (advance online publication)
doi: 2025 https://doi.org/10.1111/1749-4877.70043
https://onlinelibrary.wiley.com/doi/10.1111/1749-4877.70043


Elongated tails are exaggerated ornaments observed in various bird species, and their functional and evolutionary dynamics have attracted considerable attention. Empirical studies consistently show that sexual selection is a major drive of tail elongation. However, the genetic basis of this trait remains poorly understood. To address this gap, we performed comparative genomic analyses of 23 bird species, including 7 with extremely long tails and 16 with relative short tails. Genes related to feather development exhibited amino acid convergence replacement (e.g., APC) or displayed faster evolutionary rates (e.g., LEF1, WISP3) in the long-tailed species. Importantly, we identified convergence replacements of amino acids and rapid evolution in genes related to reproductive functions (e.g., PAQR7) and immunity (e.g., ADA), suggesting that elongated tails may serve as honest signals of genetic quality. In conclusion, this study provides genomic evidence supporting the role of sexual selection in the evolution of elongated tails, revealing an intricate interplay between sexually selected traits, fitness, and immune competence.

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