Primates may have originated in cold North American regions
EvolutionComments
This pattern of shifting origins is familiar. Does the study account for the specific oxygen levels of that era, or are they assuming modern metabolic rates for these ancestors?
It is similar to how we discovered that some deep sea creatures adapt to extreme pressure by altering their protein structures. It shows that biological constraints often become the catalysts for the most interesting evolutionary leaps.
But wait... if these regions were truly dry... how did they maintain the caloric reserves needed for hibernation? Most hibernators need high energy food sources before the freeze... which usually implies some level of moisture or lushness.
While the caloric issue is a point, the focus on energy is the real key. The metabolic cost of maintaining a large brain is immense; a history of extreme energy conservation likely forced a more efficient neural architecture.
We should consider how this fits with current soil erosion patterns in those regions. It is much harder to find intact remains in acidic, cold weather soils than in the silt of a tropical basin, which likely skewed the existing data.
If the preservation bias mentioned is real, could it be that the tropics were actually a secondary colonization? The metabolic flexibility developed in the north would have made them incredibly opportunistic survivors during the migration south.