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The present study aimed to identify the selection signature associated with temperature adaptation in Iranian sheep breeds raised in cold and hot environments. The Illumina HD ovine SNP600K BeadChip genomic arrays were utilized to analyze 114 animals from eight Iranian sheep breeds, namely Ghezel, Afshari, Shall, Sanjabi, Lori-Bakhtiari, Karakul, Kermani, and Balochi. All animals were classified into two groups: cold-weather breeds and hot-weather breeds, based on the environments to which they are adapted and the regions where they have been raised for many years. The unbiased FST (Theta) and hapFLK tests were used to identify the selection signatures. The results revealed five genomic regions on chromosomes 2, 10, 11, 13, and 14 using the FST test, and three genomic regions on chromosomes 10, 14, and 15 using the hapFLK test to be under selection in cold and hot groups. Further exploration of these genomic regions revealed that most of these regions overlapped with genes previously identified to affect cold and heat stress, nervous system function, cell division and gene expression, skin growth and development, embryo and skeletal development, adaptation to hypoxia conditions, and the immune system. These regions overlapped with QTLs that had previously been identified as being associated with various important economic traits, such as body weight, skin color, and horn characteristics. The gene ontology and gene network analyses revealed significant pathways and networks that distinguished Iranian cold and hot climates sheep breeds from each other. We identified positively selected genomic regions in Iranian sheep associated with pathways related to cell division, biological processes, cellular responses to calcium ions, metal ions and inorganic substances. This study represents the initial effort to identify selective sweeps linked to temperature adaptation in Iranian indigenous sheep breeds. It may provide valuable insights into the genomic regions involved in climate adaptation in sheep. [ABSTRACT FROM AUTHOR]

This study aims to investigate the change in spectral patterns of droughts in Iran based on the concepts of reliability, resilience, and vulnerability (RRV) in the context of time. To achieve this goal, RRV values were first estimated based on monthly gridded soil moisture data for a period of 64 years (1955–2018) for the framework of Iran's political borders. The pairwise comparison of the values of the three variables RRV indicates a positive relationship between reliability–resilience and a negative relationship between reliability–vulnerability and resilience–vulnerability. In order to obtain the Joint Probability Distribution between reliability–vulnerability, Drought Management Index (DMI) for all the gridded points within Iran's political borders were calculated by fitting the Gaussian copula. According to this index, drought is an unfavourable climatic phenomenon that is associated with increased Vulnerability and decreased Reliability. The temporal and spatial changes of this index indicate that DMI values are always high for the south, east and centre of Iran and low for the western and northern half. To study the change in spectral patterns of droughts in Iran, the 64‐year period studied (1955–2018) was divided into two equal periods of 32 years. Then, using spectral analysis through Fourier transform method, the first three periodicities related to each period that had the highest powers were extracted. Finally, their periodicity was compared. The results indicated that the drought periodicities in the north‐west, north‐east, west, south‐west, and south of Iran have become longer, that is, their nature has been changed from shorter periodicities to longer ones. This change of nature in their first three periodicities has been sometimes from 2–10 years to 2–15 years, from 2–10 years to 3–30 years, and from 3–8 years to 8–15 years. However, the periodicities of droughts in the eastern, south‐eastern, and central Iran has changed from longer periodicities to shorter ones. It has been changed from 3–15 years to 2–6 years, from 3–15 years to 2–3 years, and from 3–30 years to 3–15 years. [ABSTRACT FROM AUTHOR]