Genetic characterization of captive Cuban crocodiles (Crocodylus rhombifer) and evidence of hybridization with the American crocodile (Crocodylus acutus)

The American crocodile ( Crocodylus acutus ) is a widely distributed species across coastal and brackish areas of the Neotropical region of the Americas and the Greater Antilles. Available information on patterns of genetic differentiation in C. acutus shows a complex structuring influenced by interspecific interactions (mainly hybridization) and anthropogenic actions (mostly historical hunting, recent poaching and unintentional translocation of individuals). Moreover, recent work suggests C. acutus as a complex of cryptic species with preliminary proposals for taxonomic reassignment. Until recently, most population genetics research has primarily focused on present hybrid zones with other new world crocodilians . In this study, we used data on mitochondrial DNA control region and 11 nuclear polymorphic microsatellite loci to assess the degree of population structure of C. acutus in South America, North America, Central America and the Greater Antilles. We used traditional genetic d...

Among crocodilians, Crocodylus rhombifer is one of the world’s most endangered species with the smallest natural distribution. In Cuba, this endemic species coexists with the American crocodile (Crocodylus acutus). Hybridization between these two species is well known in captivity and might occur in the wild, but has never been demonstrated genetically. Here, we combined molecular data with environmental, geographic, and fossil data to infer the evolutionary history of Crocodylus in the Cuban Archipelago, and to evaluate genealogical support for species boundaries. We analyzed seven microsatellite loci plus DNA sequence data from nuclear (RAG-1) and mitochondrial (cytochrome b and cytochrome oxidase I) genes from 89 wild-caught individuals in Cuba, Grand Cayman Island, Jamaica, and Central America, and two samples from zoo collections. Microsatellites showed evidence of introgression, suggesting potential hybridization among Cuban groups. In Cuba, C. acutus contained one mitochondrial DNA (mtDNA) haplotype, whereas C. rhombifer contained two haplotypes. MtDNA data showed that C. acutus is paraphyletic with respect to C. rhombifer, revealing 1% sequence divergence between species within Cuba vs. 8% divergence between Cuban forms and mainland C. acutus. We suggest that hybridization has been a historical as well as a current phenomenon between C. acutus and C. rhombifer. These findings suggest that long-term conservation of crocodiles in Cuba will require identification of genetically pure and hybrid individuals, and a decrease in anthropogenic activities. We also recommend more extensive morphological and genetic analyses of Cuban population to establish clear boundaries of the hybrid zone between C. acutus and C. rhombifer.

Heredity, 2014

2014

Conservation Genetics, 2012

Academia Letters, 2021

Pakine, 2024

An eminent merchant and "nouveau literacy" author and publisher in Madras (Chennai), Shahamir Shahamirian (1723-1797) was the founder of India's first Armenian printing house and author of a celebrated Armenian constitutional treatise (c. 1787) in the same city. Despite numerous studies devoted to him, hardly anything is known about his early life and his family history. How did Shahamirian acquire his legendary wealth and how does his obscure family history help illuminate his work? This essay sheds new light on the unknown parts of Shahamirian's biography. Relying on a previously unknown letter by his mother containing a lock of her hair discovered by the present author, the sunken tombstone of his father in the South China Seas, and his newly discovered will, the essay makes an exploratory study of Shahamirian's early life and its impact on his work.

Spomenica akademiku Radetu Mihaljčiću, 2024

Metoh manastira Konče nalazio se u dolini Krive Lakavice, u neposrednoj okolini samog manastira posvećenog Svetom Stefanu. Podatke o metohu donose svega dva dokumenta. Prvi je povelja cara Uroša, kojom potvrđuje dar velikog vojvode Nikole Stanjevića Hilandaru iz 1366. godine, a u kojoj se poimenice navodi 14 sela. Končanski praktik, to jest popis poseda manastirskog vlastelinstva, donosi popis ljudi i poseda u četiri sela, sva navedena u povelji cara Uroša, ali pominje i druga naselja, kao i brojne toponime i mikrotoponime, u vezi sa manastirskim metohom. Na osnovu ova dva dokumenta i kartografskog materijala, u ovom radu se razmatra metoh Konče u celosti, kao i ubikacija popisanih mesta.