Publications by Year: 2015

SAGONAS Κ, Pafilis P, Lymberakis P, Valakos ED. Trends and patterns in the feeding ecology of the widespread Balkan green lizard Lacerta trilineata (Squamata: Lacertidae) in insular and continental Greece. North-Western Journal of Zoology. 2015;11(1):117-126.
Dimaki M, Chondropoulos B, Legakis A, Valakos E, Vergetopoulos M. New data on the distribution and population density of the African Chameleon, Chamaeleo africanus and the Common Chameleon, Chamaeleo chamaeleon in Greece. Hyla. 2015;1:36-43.
Sagonas K, Pafilis P, Valakos ED. Effects of insularity on digestion: living on islands induces shifts in physiological and morphological traits in island reptiles. Naturwissenschaften. 2015;102(9-10):55.Abstract
Living on islands entails numerous challenges for animals, among which resource scarcity stands out. In order to survive, animals have to optimize energy acquisition. We examined the impact of insularity on digestion comparing a series of physiological and morphological traits of adult males between insular and mainland populations of the Balkan green lizard. Island lizards had longer gastrointestinal tracts and gut passage times and higher digestive efficiencies. The dissection of the hindgut revealed an unexpected finding, the presence of cecal valves that were more frequent in island lizards. Thanks to all above islanders retain food for longer periods and thus maximize energy income and increase the amount of the extracted nutrients. That way, they secure energy income from the limited, in time and quantity, food resources of the islands.
Michopoulou E, Nikita E, Valakos ED. Evaluating the efficiency of different recording protocols for entheseal changes in regards to expressing activity patterns using archival data and cross-sectional geometric properties. Am J Phys Anthropol. 2015;158(4):557-68.Abstract
OBJECTIVES: In the past decade there have been extensive discussions on the potential utility of entheseal changes (EC) as activity markers. Nevertheless, no study to date has compared different EC recording protocols with respect to their correlation to activity patterns. MATERIALS AND METHODS: This article records changes on fibrocartilaginous entheses of the upper limbs of 90 male skeletons from the documented Athens Collection using the Hawkey and Merbs (Int J Osteoarchaeol 5 (1995) 324-338), Mariotti et al. (Collegium Antropol 28 (2004) 145-159), and Villotte et al. (Am J Phys Anthropol 142 (2010) 224-234) recording schemes in order to determine which one exhibits the highest correlation with activity. Activity is assessed by means of the recorded profession of each individual, as well as employing cross-sectional geometric properties. Generalized Linear Models are used to explore the impact of age, body mass, and activity on EC expression. RESULTS: Our results agree with previous studies that age is the primary factor determining EC, whereas body mass is the second most influential factor. In contrast, activity in the form of profession or cross-sectional geometry rarely showed a significant correlation to EC expression and no clear pattern could be discerned irrespective of the recording technique. However, bilateral differences in the impact of age and body mass in EC expression were traced and may relate to activity patterns. CONCLUSIONS: The differences found in the bilateral impact of age and body mass highlight the fact that the activity patterns of the individuals under examination must play an underlying role to EC expression, though current recording schemes for EC do not capture this, rendering further work in the direction of developing more elaborate recording standards imperative.