3D modeling and printing were used to create the mounted skeleton of a Pliocene proboscidea, Stegodon miensis and an Early Cretaceous titanosauriform sauropod, Tambatitanis amicitiae. Both S. miensis and T. amicitiae are known only from partial skeletons, which preserve less than one third of the total number of skeletal elements. To reconstruct their skeletons, the unfound skeletal parts should be modeled, using the modification of 3D digital data of fossil bones (virtual bones) of closely related taxa.
 In case of S. miensis, a complete skeleton of S. huanghensis is available as a template. The virtual bones of several individual of S. miensis replace the corresponding elements of the template. The virtual bones of S. miensis and those of S. huanghensis are modified so as to articulate each other.
 T. amicitae is known only from the holotype partial skeleton. As there is no titanosauriform known from a complete skeleton, partial skeletons of various titanosauriform dinosaurs were used in the modeling of unfound skeletal parts of T. amicitae.
 Completed virtual skeletons of S. miensis and T. amicitae were finally printed in real size using 3D printers and mounted in museums.

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 Paleontological specimens are three-dimensional in nature. However, certain characteristics cannot be represented by two-dimensional describing techniques. Body fossils have been collected and stored in the museums for research activity. However, fewer ichnological specimens have been collected compared to body fossils because of the difficulties associated with removing them from the site. This is problematic for comparative taxonomy in ichnology. Moreover, large tracksite documentation require huge amounts of time. Development in 3-D technology in last two decades is remarkable, solving many problems in ichnology. The authors review the basic and classic techniques of footprint study, and introduce new 3-D technology applicable to ichnological study. The authors also try to discuss the basic attitude to manage the ichnological data, because that attitude is still (or even more) important for using digital 3-D techniques.

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 The food habits of terrestrial mammals are closely related to their habitats. Therefore, the dietary reconstruction of fossil mammals provides various kinds of ecological information in addition to information pertaining to their diet. The cheek teeth of mammals have been one of the most important materials for these studies. Recently, two methods have been developed for the dietary reconstruction of mammals from their cheek teeth. The first method is mesowear analysis, which is based on the observation of the shape of the cusp that is worn during mastication. This method is especially suitable for dealing with a large number of herbivore fossils. The second method is three-dimensional microwear analysis. This method quantifies the size and shape of the micro-level scars remaining on the surface of the tooth enamel as indicators of the food habits of mammals.
 This paper reviews the methodologies of dietary reconstruction of mammals based on their tooth wear patterns, and reports the new insights obtained from these methods.

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 We describe a fossil left upper canine of a walrus (odobenid) collected from the Tsugaru Strait off the Kazamaura-mura Hebiura Fishing Port. It is identified as that of an odobenine walrus because of the size and morphological features : an elongated canine consisting of dentin covered with a thin cementum on its surface and it has a widely opened pulp cavity. This is the first record of the odobenine walrus from northern Honshu Island. It was recovered from 80 m depth by gill net, but the extant shellfish Porterius dalli and Anomia chinensis that were adhered to the surface of the specimen. These shellfishes live in shallow seas of less than 20 m depth, indicating that the canine had previously been located in shallower waters.
 The result of AMS14C dating of the specimen was 16,275 ± 45 yr BP (17,347-17,007 cal BC: Marine 13). Since it is estimated the surface water reservoir age during the Bølling-Allerød period to be ~1000 yr or more in the region off northern Japan, the specimen is considered to be a fossil walrus that went south to the Tsugaru Strait during the age of Heinrich event 1 (ca. 16.5 cal BP).

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