Complex sentence: Based on the fossil recordin South Australia, the earliest platypus fossil (Obdurodon insignis), which dates to the Miocene period, it appears that this transition has been extremely slow, supporting the theory of classical natural selection, rather than punctuated equilibrium.
Split into simpler sentences: Based on the fossil record iof South Australia, the earliest platypus fossil (Obdurodon insignis), dates to the Miocene period. It appears that this transitional phase has been unusually slow, supporting the theory of classical natural selection, rather than punctuated equilibrium.