Spatial Ecology and Diel Activity of European Wildcat (Felis silvestris) in a Protected Lowland Area in Northern Greece.

The Balkan populations of the European wildcat are among the least studied. This study reports the first findings on the spatial ecology and activity pattern of the wildcat in Greece and compares them to those of better studied northern populations. We fitted five wildcats (two males, three females) with collars containing GPS and accelerometer loggers (E-obs 1A) and collected data from fall to early summer. All animals moved within a mosaic of lowland agricultural fields, woodland patches, riparian forests and wetlands near the banks of a lake. The trapping rate was the highest reported for the species. The home range sizes, estimated using Brownian bridge movement models, ranged from 0.94 to 3.08 km2 for females and from 1.22 to 4.43 km2 for males. Based on overall dynamic body acceleration (ODBA) values estimated from the accelerometer data, the diel activity of male wildcats followed the species' typical nocturnal pattern with crepuscular peaks. Female activity varied seasonally, at times being cathemeral. We found only weak effects of environmental variables on wildcat activity, and no significant difference in the activity in open versus forested areas. Our findings suggest that human modified landscapes can play a significant role in the conservation of this typically forest-associated species.

Locomotion, postures, substrate use, and foot grasping in the marsupial feathertail glider Acrobates pygmaeus (Diprotodontia: Acrobatidae): Insights into early euprimate evolution.

Debates on early euprimate evolution are related to the understanding of the ecological context that promoted their unique adaptations. Currently, these discussions mainly revolve around the habitual use of the small-branch niche or the frequent utilization of wider, and probably, strongly inclined substrates by euprimate ancestors. The current fossil evidence implies a diversity of arboreal quadrupedal behaviors for these early euprimates, associated with the use of various types of substrates. However, inferring the positional behavior of early euprimates based exclusively on fossils fails to unravel the positional flexibility in terms of modes and substrate use, which is important for understanding key adaptations related to limb postures. Following previous research, we studied the positional behavior, substrate use and pedal grasping modes of the marsupial feathertail gliders to investigate patterns of arboreal behavior that may be analogous to those exhibited by early euprimate ancestors. For the purposes of the current study, we observed and filmed 15 male and 20 female captive adult feathertail gliders Acrobates pygmaeus (Marsupialia: Diprotodontia: Acrobatidae) in a large enclosure in the Nocturnal Pavilion of Nowe Zoo, Poznan, Poland. Our observations demonstrated a strong preference for small and for horizontal substrates, avoidance of large and of vertical ones, a diverse positional repertoire mainly composed of quadrupedalism, clambering, climbing and gliding, the last occurring from small and oblique and vertical substrates, and the dominant use of hallucal grasping, especially on small, horizontal and oblique substrates. We thus consider that the generalized profile of A. pygmaeus could fit in a stage where the euarchontan heritage of vertical clawed activities on large substrates has decreased in favor of the use of small moderately inclined substrates efficiently negotiated by diagonal sequence quadrupedalism and handled via an apparently powerful hallucal grasp. Competent use of small substrates could have further expanded into small vertical substrates, which would progressively serve as new climbing platforms and takeoff perches for unspecialized leaping. We feel that this stage may have occurred early in euprimate evolution, as small body size likely provided the necessary behavioral flexibility to exploit various niches. Depending on alternative scenarios, it could represent that of the common ancestor of euprimates or be rooted at the base of strepsirrhine evolution. This study underscores the important of analyzing the behavior of extant models to infer the locomotor evolution of euarchontans, primates or euprimates.

Arboreal Locomotion in Eurasian Harvest Mice Micromys Minutus (Rodentia: Muridae): The Gaits of Small Mammals.

Body size imposes significant constraints on arboreal locomotion. Despite the wealth of research in larger arboreal mammals, there is a lack of data on arboreal gaits of small mammals. In this context, the present study explores arboreal locomotion in one of the smallest rodents, the Eurasian harvest mice Micromys minutus (∼10 g). We examined gait metrics (i.e., diagonality, duty factor [DF], DF index, velocity, stride length, and stride frequency) of six adult male mice on simulated arboreal substrates of different sizes (2, 5, 10, and 25 mm) and inclinations (00 and 450 ). Micromys minutus employed slow, lateral sequence symmetrical gaits on the smaller substrates, which shifted to progressively faster symmetrical gaits of higher diagonality on larger substrates. Both ascents and descents were associated with a higher diagonality, and ascents with a higher DF index compared to horizontal locomotion, underscoring the role of the grasping hind feet. Velocity increase was brought about primarily by an increase in stride frequency, a pattern often encountered in other small mammals, with a secondary and significant contribution of stride length. These findings indicate that, except for velocity and the way it is regulated, there are no significant differences in gait metrics between larger and smaller arboreal mammals. Moreover, the locomotor adaptations of Eurasian harvest mice represent behavioral mechanisms that promote stable, safe, and continuous navigation along slender substrates and ultimately contribute to the successful exploitation of the arboreal milieu.

Diagonal gaits in the feathertail glider Acrobates pygmaeus (Acrobatidae, Diprotodontia): Insights for the evolution of primate quadrupedalism.

Research on primate origins has revolved around arboreality and, more specifically, the adaptations that are linked to safe navigation in the fine-branch niche. To this end, extant non-primate mammals have been used as models to assess the significance of these adaptations. However, the size of these models is larger than that estimated for early primates. In contrast, the feathertail marsupial glider Acrobates pygmaeus, with a body mass of 12 g, a clawless opposable hallux, and terminal branch feeding habits appears more suited to modeling behavioral adaptations to the small branch milieu. Analysis of video recordings of 18 feathertail gliders walking on poles of variable diameter and inclination revealed that they preferentially used diagonal sequence gaits, fast velocities and low duty factors. Diagonal gaits did not correlate to duty factor, but increased as substrate size decreased, and from descending to ascending locomotion. Furthermore, the duty factor index increased in more diagonal gaits and ascending locomotion. Finally, velocities were lower on smaller substrates, and were mainly regulated by stride frequency and, to a lesser degree, stride length. Feathertail glider gaits displayed noteworthy behavioral convergences with primate quadrupedalism, but some of these results need additional investigation. Despite any discrepancies, these features appear to be favorable for quadrupedal progression on small branches, providing a selective advantage for navigating within a fine branch niche and highlighting the importance of small body size in early primate evolution.