I. Linking lemma, critical chain, non-trivial wandering domains
II. Historic behavior in non-trivial wandering domains

We give an answer to a version of the open problem of Takens in [Nonlinearity, 21 (2008), no.3,T33-T36] which is related to historic behavior of dynamical systems. To obtain the answer, we show the existence of non-trivial wandering domains near a homoclinic tangency, which is conjectured by Colli and Vargas [Ergod. Th. & Dynam. Sys., 21 (2001), 1657-1681]. Concretely speaking, it is proved that any Newhouse open set in the Cr topology of two-dimensional diffeomorphisms with r ≧2 is contained in the closure of the set of diffeomorphisms which have non-trivial wandering domains whose forward orbits have historic behavior. Moreover, this result implies an answer in the Cr category to one of the open problems of van Strien [Discrete Conti. Dynam. Sys., 27 (2010), no.2, 557-588] which is concerned with wandering domains for Hénon family. The paper is available at http://arxiv.org/abs/1503.06258.