Final answer:
The 'breast tooth' relative of the Mammoth during the Pleistocene epoch is the Mastodon. Despite being part of the Elephantidae family and sharing similarities, these two distinct species had different tooth structures and dietary habits.
Step-by-step explanation:
The Pleistocene epoch, also known as the Ice Age, is fascinating and renowned for its mega fauna. The Mammoth is indeed one of the most well-known animals from this era. The 'breast tooth' relative to which the question refers is the Mastodon.
The Mammoth and the Mastodon, both part of the Elephantidae family, shared this epoch. However, they are distinguishing in certain features, amongst which – and relevant to the context of your question – we find that a defining characteristic of the Mastodon is the conical shape of their teeth, which in greek translates to 'breast tooth'.
These mammals, despite their similar size and appearance, have different dietary habits as well, which are largely attributed to their diverse tooth structures. Large herbivores like the Mammoth and Mastodon, were both heavily reliant on their dentition for survival.
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