Local environmental conditions under dense canopy are known to result in depletion in 13 C abundance in plants compared to an open land context. This canopy effect has been observed in tropical as well as in midlatitude forest ecosystems. However, the impact of the canopy effect on tissue 13 C abundance of temperate and boreal forest-dwelling herbivores has not been thoroughly explored. Nevertheless, the canopy effect has been suggested to explain a decrease of about 3‰ in collagen δ 13 C values in ancient large herbivores from western Europe during the forest expansion of the Late-Glacial-Early Holocene period (ca. 15,000-6000 cal BP). Some papers have considered the 13 C decrease in large herbivore as the main result of global change in atmospheric CO 2 content. A detailed review of δ 13 C values of large herbivores (reindeer, red deer, roe deer, and bison) from open and closed environments from high and mid-latitudes confirm that the canopy effect observed in plants is passed on to their consumers. In the Paris Basin, the decline in δ 13 C values of large herbivores at the Late-Glacial/Early Holocene transition around 10,000 years BP appears to be different according to the considered species, namely red deer, roe deer, and large bovines (bison and aurochs). Moreover, differences in the pattern of decrease in δ 13 C values are observed in red deer between French northern Alps and French Jura. These differences among species in their isotopic response through time for a given geographical location, and within species from different locations, suggest variance in ecological responses of species that are associated with the relative use of forested habitat. As a result, 13 C abundances in collagen can be considered as a direct tracker of the degree of closure of the habitat of ancient herbivores.

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Microevolutionary trends in dental traits were studied in a Polish population of the Red fox, Vulpes vulpes (Linnaeus, 1758). Changes in qualitative and quantitative traits over a 70‐year interval were analysed in 1453 museum specimens collected between 1927 and 1996. Over that period, there were qualitative trends towards increasing complication of occlusal crown surface in posterior premolars (i.e. P4, P3, P4) and I3. Other cheek teeth did not undergo directional change. Changes in trait correlations were assessed using samples from the 1960s and 1990s. The correlations between C1–C1 and M1–M2 increased, while correlation values in the incisor region (I1–I2, I1–I1, I1–I2, I3–I2), carnassial region (P4–M1, P4–M1 and M1–M1) and in P2–P1 decreased. These changes may be related to increasing dietary opportunism of the Red fox during the 20th century.