Genomic bases of insularity and ecological divergence in barn owls (Tyto alba) of the Canary Islands

Islands, and the particular organisms that populate them, have long fascinated biologists. Due to their isolation, islands offer unique opportunities to study the effect of neutral and adaptive mechanisms in determining genomic and phenotypical divergence. In the Canary Islands, an archipelago rich in endemics, the barn owl (Tyto alba) is thought to have diverged into a subspecies (T. a. gracilirostris) on the eastern islands, Fuerteventura and Lanzarote. Taking advantage of 40 whole-genomes and modern population genomics tools, we provide the first look at the origin and genetic makeup of barn owls of this archipelago. We show that the Canaries hold diverse, long-standing and monophyletic populations with a neat distinction of gene pools from the different islands. Using new method, less sensitive to structure than classical FST, to detect regions involved in local adaptation to the insular environment, we identified a haplotype-like region likely under positive selection in all Canaries individuals. Genes in this region suggest morphological adaptations to insularity. In the eastern islands, where the subspecies T. a. gracilirostris is present, genomic traces of selection pinpoint signs of locally adapted body proportions and blood pressure, consistent with the smaller size of this population living in a hot arid climate. In turn, genomic regions under selection in the western barn owls from Tenerife showed an enrichment in genes linked to hypoxia, a potential response to inhabiting a small island with a marked altitudinal gradient. Our results illustrate the interplay of neutral and adaptive forces in shaping divergence and early onset speciation.

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Population genomics of apricots unravels domestication history and adaptive events

Nature Communications ◽

10.1038/s41467-021-24283-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Alexis Groppi ◽

Shuo Liu ◽

Amandine Cornille ◽

Stéphane Decroocq ◽

Quynh Trang Bui ◽

...

Keyword(s):

Population Genomics ◽

Fruit Trees ◽

Prunus Armeniaca ◽

Genetic Maps ◽

Phenotypic Traits ◽

Gene Pools ◽

High Genetic Diversity ◽

Asian Populations ◽

Selected Traits ◽

Genomic Regions

AbstractAmong crop fruit trees, the apricot (Prunus armeniaca) provides an excellent model to study divergence and adaptation processes. Here, we obtain nearly 600 Armeniaca apricot genomes and four high-quality assemblies anchored on genetic maps. Chinese and European apricots form two differentiated gene pools with high genetic diversity, resulting from independent domestication events from distinct wild Central Asian populations, and with subsequent gene flow. A relatively low proportion of the genome is affected by selection. Different genomic regions show footprints of selection in European and Chinese cultivated apricots, despite convergent phenotypic traits, with predicted functions in both groups involved in the perennial life cycle, fruit quality and disease resistance. Selection footprints appear more abundant in European apricots, with a hotspot on chromosome 4, while admixture is more pervasive in Chinese cultivated apricots. Our study provides clues to the biology of selected traits and targets for fruit tree research and breeding.

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Landscape and climatic variations of the Quaternary shaped multiple secondary contacts among barn owls (Tyto alba) of the Western Palearctic

10.1101/2021.06.09.447652 ◽

2021 ◽

Author(s):

Tristan Cumer ◽

Ana Paula Machado ◽

Guillaume Dumont ◽

Vasileios Bontzorlos ◽

Renato Ceccherelli ◽

...

Keyword(s):

Contact Zone ◽

Population Genomics ◽

Secondary Contact ◽

Tyto Alba ◽

The Balkans ◽

Climatic Variations ◽

Last Glaciation ◽

Western Palearctic ◽

Barn Owls ◽

History Of

The combined actions of climatic variations and landscape barriers shape the history of natural populations. When organisms follow their shifting niches, obstacles in the landscape can lead to the splitting of populations, on which evolution will then act independently. When two such populations are reunited, secondary contact occurs in a broad range of admixture patterns, from narrow hybrid zones to the complete dissolution of lineages. A previous study suggested that barn owls colonized the Western Palearctic after the last glaciation in a ring-like fashion around the Mediterranean Sea, and conjectured an admixture zone in the Balkans. Here, we take advantage of whole-genome sequences of 94 individuals across the Western Palearctic to reveal the complex history of the species in the region using observational and modeling approaches. Even though our results confirm that two distinct lineages colonized the region, one in Europe and one in the Levant, they suggest that it predates the last glaciation and identify a narrow secondary contact zone between the two in Anatolia. Nonetheless, we also show that barn owls re-colonized Europe after the glaciation from two distinct glacial refugia: a western one in Iberia and an eastern one in Italy. Both glacial lineages now communicate via eastern Europe, in a wide and permeable contact zone. This complex history of populations enlightens the taxonomy of Tyto alba in the region, highlights the key role played by mountain ranges and large water bodies as barriers and illustrates the power of population genomics in uncovering intricate demographic patterns.

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Contamination by neonicotinoid insecticides in barn owls (Tyto alba) and Alpine swifts (Tachymarptis melba)

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.147403 ◽

2021 ◽

Vol 785 ◽

pp. 147403

Author(s):

Ségolène Humann-Guilleminot ◽

Shirley Laurent ◽

Pierre Bize ◽

Alexandre Roulin ◽

Gaétan Glauser ◽

...

Keyword(s):

Tyto Alba ◽

Neonicotinoid Insecticides ◽

Barn Owls

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Nidicolous beetle species richness is driven by Barn Owl’s nests occupancy and landscape structure

Journal of Ornithology ◽

10.1007/s10336-021-01875-z ◽

2021 ◽

Author(s):

Vivien Cosandey ◽

Robin Séchaud ◽

Paul Béziers ◽

Yannick Chittaro ◽

Andreas Sanchez ◽

...

Keyword(s):

Species Richness ◽

Landscape Structure ◽

Barn Owl ◽

Arthropod Community ◽

Tyto Alba ◽

Nest Material ◽

Crop Fields ◽

Nest Boxes ◽

Bird Droppings ◽

Barn Owls

AbstractBird nests are specialized habitats because of their particular composition including nest detritus and bird droppings. In consequence, they attract a specialized arthropod community considered as nidicolous, which includes species only found in bird nests (strictly nidicolous) or sometimes found in bird nests (facultatively nidicolous). Because the factors influencing the entomofauna in bird nests are poorly understood, in autumn 2019, we collected nest material in 86 Barn Owl (Tyto alba) nest boxes. We investigated whether the invertebrate species richness was related to Barn Owl nest box occupancy, the density of available nest boxes and the landscape structure. We found 3,321 nidicolous beetle specimens belonging to 24 species. Species richness of strictly nidicolous beetles was 2.7 times higher in nest boxes occupied by a family of Barn Owls the previous spring compared to unoccupied nest boxes. It was also higher in sites that were more often occupied by Barn Owls in the five previous years and in areas surrounded by a higher proportion of crop fields. For facultatively nidicolous beetles, the density of Barn Owl nest boxes enhanced the species richness. In conclusion, our study suggests that the strictly nidicolous beetles benefit from occupied nest boxes of Barn Owls, whereas facultatively nidicolous beetles look for nest boxes independently of whether Barn Owls occupy them. Our study highlights the importance of bird nests for a suite of invertebrates.

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Late-Holocene asynchronous extinction of endemic mammals on the eastern Canary Islands

The Holocene ◽

10.1177/0959683611430414 ◽

2011 ◽

Vol 22 (7) ◽

pp. 801-808 ◽

Cited By ~ 7

Author(s):

Juan Carlos Rando ◽

Josep Antoni Alcover ◽

Jacques Michaux ◽

Rainer Hutterer ◽

Juan Francisco Navarro

Keyword(s):

Canary Islands ◽

Late Holocene ◽

Middle Age ◽

Rattus Rattus ◽

Tyto Alba ◽

Isolated Populations ◽

European Contact ◽

Black Rat ◽

Local Extinctions ◽

Ams Dating

The Lava mouse ( Malpaisomys insularis), and the Canarian shrew ( Crocidura canariensis) are endemic of the Eastern Canary Islands and islets. The former is extinct while Canarian shrew survives in the two main islands and two islets. In order to provide insights regarding causes and processes contributing to the extinction of these endemic mammals: (i) we established last occurrence dates for Lava mouse, and first records for two exotic species – House mouse ( Mus musculus) and Black rat ( Rattus rattus) – through direct 14C AMS dating of collagen from bones; (ii) we analysed recent material from Barn owl ( Tyto alba gracilirostris) roosting sites to evaluate its impact on Canarian shrew in the presence of introduced rodents. The new data strongly suggest that the extinction of Lava mouse was the result of an accumulative process of independent disappearances (or ‘local extinctions’) affecting the isolated populations. The timing of the introduction of the Black rat on the main islands (before Middle Age European contact in Lanzarote and after Middle Age European contact in Fuerteventura) matches with the last occurrence dates for the presence of Lava mouse on these islands, and are very probably their cause. The losses of these Lava mouse populations occurred in an asynchronous way, spreading across at least six centuries. On small islands, hyperpredation emerges as the most plausible process to explain the disappearance of the Lava mouse in the absence of rat populations, although stochastic processes can not be definitively excluded.

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Diet of Barn Owls (Tyto alba) in Northern Belize

The Southwestern Naturalist ◽

10.1894/mh-43.1 ◽

2009 ◽

Vol 54 (1) ◽

pp. 104-107 ◽

Cited By ~ 4

Author(s):

Steven G. Platt ◽

Thomas R. Rainwater ◽

Daniel J. Leavitt ◽

Stanlee M. Miller

Keyword(s):

Tyto Alba ◽

Barn Owls

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Population genomics of parallel hybrid zones in the mimetic butterflies, H. melpomene and H. erato

10.1101/000208 ◽

2013 ◽

Author(s):

Nicola Nadeau ◽

Mayte Ruiz ◽

Patricio Salazar ◽

Brian Counterman ◽

Jose Alejandro Medina ◽

...

Keyword(s):

Population Genomics ◽

De Novo ◽

Reference Sequence ◽

Colour Pattern ◽

Adaptive Divergence ◽

Population Divergence ◽

Hybrid Zones ◽

Data Alignment ◽

Parallel Hybrid ◽

Genomic Regions

Hybrid zones can be valuable tools for studying evolution and identifying genomic regions responsible for adaptive divergence and underlying phenotypic variation. Hybrid zones between subspecies of Heliconius butterflies can be very narrow and are maintained by strong selection acting on colour pattern. The co-mimetic species H. erato and H. melpomene have parallel hybrid zones where both species undergo a change from one colour pattern form to another. We use restriction associated DNA sequencing to obtain several thousand genome wide sequence markers and use these to analyse patterns of population divergence across two pairs of parallel hybrid zones in Peru and Ecuador. We compare two approaches for analysis of this type of data; alignment to a reference genome and de novo assembly, and find that alignment gives the best results for species both closely (H. melpomene) and distantly (H. erato, ~15% divergent) related to the reference sequence. Our results confirm that the colour pattern controlling loci account for the majority of divergent regions across the genome, but we also detect other divergent regions apparently unlinked to colour pattern differences. We also use association mapping to identify previously unmapped colour pattern loci, in particular the Ro locus. Finally, we identify within our sample a new cryptic population of H. timareta in Ecuador, which occurs at relatively low altitude and is mimetic with H. melpomene malleti.

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