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The control region (CR) regulates the replication and transcription of the mitochondrial genome (mitogenome). Some avian mitogenomes possess two CRs, and the second control region (CR2) may enhance replication and transcription; however, the CR2 in lark mitogenome appears to be undergoing loss and is accompanied by tandem repeats. Here, we characterized six lark mitogenomes from Alaudala cheleensis, Eremophila alpestris, Alauda razae, and Calandrella cinerea and reconstructed the phylogeny of Passerida. Through further comparative analysis among larks, we traced the evolutionary process of CR2. The mitochondrial gene orders were conserved in all published lark mitogenomes, with Cytb-trnT-CR1-trnP-ND6-trnE-remnant CR2 with tandem repeat-trnF-rrnS. Phylogenetic analysis revealed Alaudidae and Panuridae are sister groups at the base of Sylvioidea, and sporadic losses of CR2 may occur in their common ancestor. CR sequence and phylogeny analysis indicated CR2 tandem repeats were generated within CR2, originating in the ancestor of all larks, rather than inherited from CR1. The secondary structure comparison of tandem repeat units within and between species suggested slipped-strand mispairing and DNA turnover as suitable models for explaining the origin and evolution of these repeats. This study reveals the evolutionary process of the CR2 containing tandem repeat in Alaudidae, providing reference for understanding the evolutionary characteristics and dynamics of tandem repeats. [ABSTRACT FROM AUTHOR]

The Kihansi Spray Toad (KST) Nectophrynoides asperginis is endemic to the unique wetland habitat surrounding the Kihansi Falls, Tanzania, with which it was associated. The species was declared extinct in the wild in 2009 by the International Union for Conservation of Nature (IUCN), following the loss of its unique habitat due to the diversion of the Kihansi River for hydropower production. This study is an initial attempt to determine the survivorship and possible sources of mortality of newborn and adult KSTs placed in cages in their original habitat in the Upper Spray Wetland (USW) and Lower Spray Wetland (LSW) areas. The cages were made of wooden frames covered with galvanized wire mesh to prevent the toads from escaping while allowing their prey (live invertebrates) to enter. There was a significantly higher survivorship of adult toads in the USW (29.2%) compared to those in the LSW (4.2%) (χ² = 36.7, DF = 1, P < 0.0001). The newborn toads showed equally high survivorship rates in both USW (70%) and LSW (80%) (χ² = 0.1441, DF = 1, P = 0.7042). Newborn toads had a higher survivorship (75%) than adults (17%) (χ² = 16.7, DF = 1, P < 0.0001). Thus, we conclude that newborns were the more suitable life-stage for successful reintroduction of the KST back into its natural habitat. Therefore, we recommend continual reintroduction of newborn toads until the population stabilizes. Further studies should be conducted on other factors affecting the population dynamics of released KST, such as predation, diseases and both inter- and intra-specific competition. Maintenance of the habitat and constant monitoring programmes for the reintroduced KST should be continued. [ABSTRACT FROM AUTHOR]