Dinosaur migration and their habitat environments in Japanese Cretaceous and its adjacent area

东亚可能存在两种“恐龙高速公路”模式，表明恐龙迁徙和/或定居；(2) Gnu模型：恐龙在朝鲜半岛南部和中国东部之间的季节性迁移。这类似于现代gnu迁移。本项目的目的是验证这些模型，并研究恐龙高速公路上的恐龙栖息地环境。结果表明：(1)鸟取群兽脚亚目和鸟脚亚目足迹与延吉群兽脚亚目足迹普遍存在。这意味着恐龙沿着两个地区之间的河流流域行走。鸟取群的环境为浅海，反映了分流湾和辫状、曲流的河流环境。根据沉积相的时间变化，鸟取群有海侵和退退两个阶段。(2)在中国辽宁省涂城子组（侏罗纪-白垩纪边界）发现了水鸟的足迹，这可能是中国最古老的鸟类证据。这些痕迹表明，在白垩纪早期，辽宁地区出现了类似滨鸟的物种。(3)新墨西哥州的莫斯奎罗溪恐龙足迹遗址为恐龙的社会行为提供了最好的例子之一。该遗址位于北美白垩纪恐龙高速公路的南部。结果表明，48条向北的轨道可以根据不同的方向划分为不同的子群，但速度变化不显著。我们还推断幼虫和亚成虫向北迁徙，亚成虫和成虫向南迁徙的优势。畜群结构的概念在技术上被检验和定义为在一个较大的群或畜群内轨道群的任何有序安排。

There are possible two models of the "Dinosaur freeway" in East Asia, suggested dinosaur migration and/or settlement ; (1) River side model : dinosaurs migrated and/or settled along the river in Asian continent, and (2) Gnu model : dinosaurs seasonally migrated between southern Korean Peninsula and east China. This was similar to modern gnu migration. The purpose of the project is to verify these models and to study an environment of the dinosaur habitat on the dinosaur freeway.We had the following results : (1) Theropod and ornithopod tracks from the Tetori Group are common in that from the Yanji Group, Far east China. This means dinosaurs walked along the fluvial valley between two areas. The environment of the Tetori Group shows sallow marine, reflect distributary bay and braided and meandering river environments. Based on facies change through time, the Tetori Group had transgression and regression phases. (2) We found out tracks of waterbirds from the Tu Cheg Zi Formation (Jurassic-Cretaceous boundary), Liaoning Province, China, that may be the oldest evidence of birds from China. The tracks suggest The presence of shorebird-like species in Liaoning region at the very beginning of the Cretaceous. (3) The Mosquero Creek dinosaur track site in New Mexico provides one of the best examples of social behavior among dinosaurs. The site is located on the southern part of the Cretaceous dinosaur freeway in North America. Our statistical analysis of trackway directions and speed estimates suggests that the 48 northerly oriented trackways can be resolved into subgroups based out differential orientations, but that speed variations are not significant. We also infer a preponderance of juveniles and subadults heading north and subadults and adults heading south. The concept of herd structure is examined and defined, ichnologically, as any orderly arrangement of trackway groupings within a larger group or herd.