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We conducted an avian survey of Mdando Forest in Tanzania´s Southern Highlands in September and November 2022, and May 2023, using mist nets and opportunistic observations from camps inside the forest at 1750m, 1950m and 2050m elevation. We recorded 61 species which included nine species that previously have not been reported from Mdando, including Black-headed Apalis Apalis melanocephala and Sharpe’s Akalat Sheppardia sharpei. Conversely, we failed to find three forest species that are recorded from Mdando. Of the total of 64 bird species known from the forest, 36 are classified as forest specialists, 24 are forest generalists and four are forest visitors. The forest avifauna included range-restricted species such as Iringa Akalat Sheppardia lowei and Spot-throat Modulatrix stictigula. The non-forested Makambako highlands (the “Makambako Gap”) have often been seen as a faunal barrier separating the Southern Highlands from the more species-rich East Arc Mountains. However, 36 of the 44 montane forest specialists known from the Udzungwa Mountains, the southernmost and closest area of the East Arc Mountains, have now been recorded from Mdando Forest, which shows that there is a large overlap in the montane avifauna on both sides of the Makambako Gap, suggesting a comparatively recent forest connection. [ABSTRACT FROM AUTHOR]

Learned traits are thought to be subject to different evolutionary dynamics than other phenotypes, but their evolutionary tempo and mode has received little attention. Learned bird song has been thought to be subject to rapid and constant evolution. However, we know little about the evolutionary modes of learned song divergence over long timescales. Here, we provide evidence that aspects of the territorial songs of Eastern Afromontane sky island sunbirds Cinnyris evolve in a punctuated fashion, with periods of stasis of the order of hundreds of thousands of years or more, broken up by evolutionary pulses. Stasis in learned songs is inconsistent with learned traits being subject to constant or frequent change, as would be expected if selection does not constrain song phenotypes over evolutionary timescales. Learned song may instead follow a process resembling peak shifts on adaptive landscapes. While much research has focused on the potential for rapid evolution in bird song, our results suggest that selection can tightly constrain the evolution of learned songs over long timescales. More broadly, these results demonstrate that some aspects of highly variable, plastic traits can exhibit punctuated evolution, with stasis over long time periods. [ABSTRACT FROM AUTHOR]

The article discusses herpetological surveys conducted at the Lichinga Plateau and Mt. Namuli, regions in northern Mozambique. Topics discussed include hyperoliid frog species Afrixalus brachycnemis and Hyperolius cf. spinigularis, the connection of Mozambican Afromontane inselbergs to the Afromontane archipelago, and discovery of range extensions and taxonomic novelties along with records of amphibians and reptiles.

Learned traits are thought to be subject to different evolutionary dynamics than other phenotypes, but their evolutionary tempo and mode has received little attention. Learned bird song has been thought to be subject to rapid and constant evolution. However, we know little about the evolutionary modes of learned song divergence over long timescales. Here, we provide evidence that aspects of the territorial songs of Eastern Afromontane sky island sunbirds Cinnyris evolve in a punctuated fashion, with periods of stasis of the order of hundreds of thousands of years or more, broken up by evolutionary pulses. Stasis in learned songs is inconsistent with learned traits being subject to constant or frequent change, as would be expected if selection does not constrain song phenotypes over evolutionary timescales. Learned song may instead follow a process resembling peak shifts on adaptive landscapes. While much research has focused on the potential for rapid evolution in bird song, our results suggest that selection can tightly constrain the evolution of learned songs over long timescales. More broadly, these results demonstrate that some aspects of highly variable, plastic traits can exhibit punctuated evolution, with stasis over long time periods.