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1
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Individual quality of wolf in some Baltic state

100%
Dziedzic R., Flis M., Beeger S., Wojcik M.
Acta Agrophysica
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2003
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tom 01
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nr 1[86]
2
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New psittacosaurid highlights skull enlargement in horned dinosaurs

80%
Sereno P. C., Xijin Z., Brown L., Lin T.
Acta Palaeontologica Polonica
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2007
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tom 52
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nr 2
A new psittacosaurid is based on a nearly complete articulated skeleton from northeastern China that differs principally in skull size as compared to the most common and widespread species, Psittacosaurus mongoliensis. The skull of Psittacosaurus majorsp. nov., is 25% larger despite very similar postcranial skeletal dimensions. Such selective skull enlargement is very unusual. Skull size in ceratopsians, in general, scales with positive allometry relative to body mass: species of greater mass have proportionately larger skulls. This pattern stands in marked contrast to that for other vertebrate herbivores, in which larger−bodied species either have proportionately similar or smaller skulls relative to body mass. Larger−bodied ceratopsians evolved skulls that are 50% or more of trunk length—as measured without their expansive cranial frill. Although contemporaneous duck−billed dinosaurs also exhibit some positive allometry in the skull, skull length remains approximately 35% of trunk length. The evolution of extraordinary absolute and relative skull size among ceratopsians appears to have been driven by sexual selection and involved the tandem evolution of reduced head mobility and an obligate quadrupedal posture.
3

Growth studies in Akodon dolores [Rodentia: Muridae] in captivity

80%
Piantanida M., Barrantes G. E.
Acta Theriologica
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1998
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tom 43
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nr 2
Growth processes in Akodon dolores Thomas, 1916 were studied by measuring morphological variables in a captive colony of 1500 specimens. Sex differences were not statistically significant. Most variables fitted to a sigmoid function and showed the same behaviour up to 3 months of age: an acceleration in growth up to the first month, followed by a deceleration up to the third month. Growth variables reached their asymptotic value after the fourth month of age. An exception was the lens weight which continually increased with age without reaching an asymptotic value. The instantaneous growth rates became less than unity at the third month of age, indi­cating that the maximal percentile growth should be before this stage. The latter was corroborated with the body weight increase and body length curves in which the inflexion point was observed at the 1-month stage. In A. dolores this stage is physiolo­gically associated with puberty and in the present study was reached when the animals achieved 40% of their adult body weight. This study is the basis of an age distribution study of A. dolores with a biological foundation.
4

Evolutionary and climatic factors affecting tooth size in the red fox Vulpes vulpes in the Holarctic

80%
Szuma E.
Acta Theriologica
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2008
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tom 53
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nr 4
Research into the geographical pattern of tooth size in the red fox,Vulpes vulpes (Linnaeus, 1758) in the Holarctic was conducted on a sample of 3806 skulls belonging to 41 fox populations. The Nearctic was represented by 948 specimens (249 females, 359 males, 340 specimens of unknown sex) belonging to 13 populations, whereas the Palearctic was represented by 2858 red foxes (1034 females, 1256 males, 568 specimens of unknown sex) from 32 populations. In the Nearctic, the largest foxes live on Kodiak Island (V. v. harrimani) and the Kenai Peninsula (V. v. kenaiensis), while the smallest ones live in California (V. v. necator) and Georgia (V. v. fulvus). In the Palearctic, the largest foxes come from the Far East (V. v. jakutensis, V. v. beringiana, V. v. tobolica), while the smallest are from the southern borders of the Eurasian range (V. v. pusilla, V. v. barbara, V. v. arabica). In both the Palearctic and Nearctic, tooth size in the fox varies depending on the geo-climatic factors. The fox’s tooth size confirms the general basis of Bergmann’s rule. In the Palearctic, specimens with larger teeth occur in cooler habitats with greater seasonality. These are first and foremost Northern and Far Eastern populations. In the Nearctic, tooth size in red foxes depends on the temperature and humidity of their habitat. Competition within the species and between species has important impact on the variation and dimorphism of tooth size in the red fox. Both in the Nearctic and Palearctic, red foxes from regions of sympatric co-occurrence with other closely relatedVulpes species, are more sexually dimorphic in terms of tooth size than red foxes from allopatric regions. Analysis of morphological distance on the basis of the size of dental characteristics shows, that in the Palearctic, the foxes from India (V. v. pusilla), while in the Nearctic, the population from Kodiak Island (V. v. harrimani) are most distant from the remaining populations. Geographic barriers such as the Bering Strait, Parry Channel, Mackenzie River, Kolyma and Omolon River systems have had a critical impact on red fox evolution. The most likely place for the evolution and diversification of the phyletic lineVulpes vulpes seems to be the Middle East region.
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