Paleontological and Paleobotanical Museum (Nostimo) teeth of a shark that was 20–25 m long, and a Late Pliocene (3.5 million years old) tooth of an "Anancus arvenensis", a mastodon, an ancient relative of the elephant, which has been recognised here for the first time in the wider area of Western Macedonia. The mastodon which lived in this area was about the same size as a modern elephant, but with longer tusks. Also displayed are some Neolithic tools (from the 4th millennium BC): a fishing weight, and a blade for harvesting crops. Paleontological and Paleobotanical Museum (Nostimo) The Paleontological and Paleobotanical Museum () at Nostimo is
Mastodon and expanded to relatively large numbers 13,000 years ago, and their hunting may have caused a gradual attrition of the mastodon population. Analysis of tusks of mastodons from the American Great Lakes region over a span of several thousand years prior to their extinction in the area shows a trend of declining age at maturation; this is contrary to what one would expect if they were experiencing stresses from an unfavorable environment, but is consistent with a reduction in intraspecific competition that would result from a population being reduced by human hunting. Mastodon Mastodons (Greek: μαστός "breast" and ὀδούς, "tooth")