Geographic variation of skeletal ontogeny and skull shape in the harbour porpoise (Phocoena phocoena)

All extant porpoise species show paedomorphic skeletal traits. These traits are hypothesized to be connected with rapid growth to reproductive size and could thus show geographic variation according to ecological circumstances. To investigate this, skeletal ontogeny was compared among harbour porpoises from California, West Greenland, the inner Danish waters, and the Sea of Azov. Porpoises from California grew to larger sizes than Danish porpoises, which were again larger than Greenlandic porpoises, whereas Azov porpoises were smallest. Size differences were largely attributable to differences in timing of offset of growth. Expression of paedomorphosis followed the same pattern among populations and sexes as adult sizes; Californian porpoises were less paedomorphic than the other populations across all assessed traits, whereas porpoises from Azov were the most paedomorphic. We propose that the larger size and less profound paedomorphism seen in Californian porpoises are attributable to fluctuation of prey availability, owing to variation in upwelling on which productivity in Californian waters depends. Skull shapes after correction for allometry were significantly different among all populations, Sea of Azov porpoises being most divergent. There was no overlap of skull shapes between the Atlantic, the Pacific, and Azov, supporting the current division of harbor porpoises ( Phocoena phocoena (L., 1758)) into three subspecies ( Phocoena phocoena phocoena (L., 1758), Phocoena phocoena relicta Abel, 1905, and Phocoena phocoena vomerina Gill, 1865).

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Western Immigration in the fourteenth-century Golden Horde: The Case of Venetian Tana

Golden Horde Review ◽

10.22378/2313-6197.2021-9-1.90-107 ◽

2021 ◽

Vol 9 (1) ◽

pp. 90-107

Author(s):

Lorenzo Pubblici ◽

Keyword(s):

Fourteenth Century ◽

Close Contact ◽

Cultural Background ◽

The Other ◽

Sea Of Azov ◽

State Archive ◽

Associative Model ◽

Western Population ◽

The Sea Of Azov ◽

The World

Objective: This paper’s aim is to reconstruct the Western population of Venetian Tana in the fourteenth century, the residents’ perception of their condition as “migrants”, and finally this population’s interactions with the other communities who lived there. Research materials: The sources used are primarily the notarial deeds of the Venice State Archive together with the vast and excellent scholarship produced in recent decades. Research results and novelty: For over two centuries the settlement of Tana, situated in the territory of the Golden Horde, represented the easternmost outpost of the Latin emporia in the Levant. Here, the utilitarian concept of the Western urban mercantile class found itself confronted with a new experience. This group was a minority living in close contact with larger, cohesive communities whose cultural background was extremely diverse. Those who emigrated east were mainly the emerging urban bourgeoisie, but also families of ancient noble origin who had nothing in common with the world of the Steppe and its traditional roots. These citizens came to the Levant, bringing with them the urban associative model. The life of the settlement at the mouth of the river Don is an ideal basis for observing the flow of people who left Venice and its surroundings on galleys and, after months of travel, arrived on the shores of the Sea of Azov.

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Growth, proportions and variation of the skull of harbour porpoises (Phocoena phocoena) from the Sea of Azov

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315407054458 ◽

2007 ◽

Vol 87 (1) ◽

pp. 271-292 ◽

Cited By ~ 5

Author(s):

P.E. Gol'din

Keyword(s):

Sexual Dimorphism ◽

Growth Patterns ◽

The Black Sea ◽

Sea Of Azov ◽

Phocoena Phocoena ◽

The Sea Of Azov ◽

Adjacent Structures ◽

Skull Growth ◽

Functional Complex ◽

Skull Measurements

Skulls of 153 porpoises from the Sea of Azov and the Black Sea were studied. Thirty-seven skull measurements were examined. Skull growth in porpoises can be divided into five periods. The greatest changes in growth patterns occur after the first weeks of life. A ‘relay effect’ in growth of some structures (e.g. rostrum) was observed. Individual variation usually increases when a given structure grows intensively; however, some structures are highly variable over the entire lifespan. Sexual dimorphism is demonstrated in most of the measurements in adult animals. Temporal variation is minor. Skull structures are characterized by six types of allometry; three of them demonstrate drastic changes of allometry during lifespan, thus requiring two allometric equations to describe them. Skull proportions change critically during the first weeks of life. Six groups of correlated measurements differing in the pattern of correlation links during ontogeny were identified. Three factors play the most important roles in forming the definitive skull proportions: correlation between adjacent structures, impact of total skull size and inclusion in a certain functional complex.

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Differences In Skull Size Of Harbour Porpoises, Phocoena phocoena (Cetacea), In The Sea Of Azov And The Black Sea: Evidence For Different Morphotypes And Populations

Vestnik Zoologii ◽

10.1515/vzoo-2015-0017 ◽

2015 ◽

Vol 49 (2) ◽

pp. 171-180 ◽

Cited By ~ 4

Author(s):

P. E. Goldin ◽

K. A. Vishnyakova

Keyword(s):

Black Sea ◽

The Black Sea ◽

Sea Of Azov ◽

Phocoena Phocoena ◽

The Sea Of Azov ◽

Skull Size ◽

The North ◽

North Eastern ◽

The Difference ◽

North Western

Abstract There are two porpoise stocks in the northern Black Sea: the north-western (Odessa Gulf) and northeastern (Crimean and Caucasian waters); in addition, another stock is in the Sea of Azov. The Azov porpoises are distinct in their body size and biology. This research was conducted on the skulls of stranded sexually mature porpoises from the north-eastern Black Sea, north-western Black Sea and the Sea of Azov. In the north-eastern Black Sea samples, both present-day and old-time, the sexual dimorphism of the skull size was not significant, whereas in the Sea of Azov the females were significantly larger than males. The Azov skulls were strongly different from those from the Black Sea: they were larger, proportionally wider and had the wider rostra; also, there was no significant chronological variation within the Black Sea. The Azov and Black Sea samples were classified with the 100 % success with four variables. The northwestern Black Sea skulls were somewhat intermediate in their characteristics between the Azov and northeastern Black Sea samples, but they were classify ed together with other Black Sea specimens. The difference between the Azov and Black Sea skulls was greater than between many North Atlantic populations, despite the extreme geographical proximity of the two stocks. The low variation within the Black Sea supports the earlier conclusions on the lack of genetic variation: all the Black Sea stocks are expected to be genetically similar sub-populations, whereas the Azov and Marmara stocks possibly represent the genetically distant populations. The porpoises from the Black Sea and the Sea of Azov equally show the traits which characterize the subspecies Phocoena phocoena relicta, but the Black Sea porpoises appear to be more paedomorphic in terms of ontogenetic trajectories.

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