Respuesta :
Answer: Yes the author think big brains evolved in primates to aid them in getting food for survival
Explanation:
INTRODUCTION :
Primate evolution has been dominated, as much as anything, by unusually large brains. Over 40 years, many explanations for the evolution of large brains have been proposed. these explanations are divided into four major types , each with many hypotheses of their own:
(1) genetic explanations (primates have large brains because a particular gene mutation allows them to grow large brains)
(2) developmental explanations (primates have large brains because their extended periods of parental investment allow them to grow large brains),
(3) ecological explanations (primates evolved large brains in order to cope with
demanding environmental conditions)
(4) social explanations (there is something intrinsically complex about primate sociality that requires a large brain).
PREFERRED HYPOTHESIS:
The Preferred Hypothesis is Instrumental hypotheses;
These hypotheses focus mainly on the demands of food finding and implicitly (but almost never explicitly) assume that foraging is the single most important constraint on an animal’s fitness. In effect, this is the default position for ecologists In early analyses, It was assumed to be cognitively more demanding than folivory, and it may well be: fruits are less predictable in time and space than leaves. However, phylogenetic comparative analyses find no relationship between the degree of dietary frugivory and brain size when controlling for social group size across mammals though the latter fact may be the crucial giveaway in that it may indicate that a change of diet is needed when large groups are involved because of the effect that group size has on energetics.
More importantly, perhaps, for smart foraging to have any traction as an explanation, it is necessary to show that primates do something different from non-primates otherwise why would they need bigger brains than other mammals? For this reason, more recent studies have focused on foraging innovations, including the discovery and exploitation of novel foods or novel means of accessing foods . A number of analyses have shown that foraging innovations correlate with brain size in both birds and primates and this relationship has in turn been related to species’ abilities to survive in challenging habitats. The weakness of this claim is that most taxa do not in fact exhibit much smart foraging or technical innovativeness, despite variation in brain size across species. The crucial fact is that, in primates, the relationship seems to be more of a phase transition: most species exhibit no innovations at all and a few exhibit a lot. With this, it would seem to be stretching a point to claim that what is in effect a dichotomy in innovativeness is responsible for a quantitative change in brain size across the entire order. An obvious alternative explanation might be that smart foraging is a by-product of acquiring a brain of a particular minimum brains certainly provide the capacity to engage in efficient trial-and-error problem-solving or insightful one-trial learning.
More Crucial issue concerns the assumption that food is, or byextension energy budgets are, the primary factor influencing an animal’s fitness, either because all other extrinsic effects are trivial by comparison or because foraging is the only factor that an animal can actually control through its behaviour.
WHY BIG BRAINS EVOVLED IN PRIMATES?
In terms of brain evolution, developmental constraints have focused on life-history traits and neurogenic explanations, but more recently genetic explanations (and especially those genes associated with accelerated evolution within the human lineage have joined this set. Evolutionary constraints can also involve the physiological costs to grow and maintain traits. Brains are extremely expensive, and these constraints represent some of the costs that animals must be able absorb in order to evolve large brains if they have a compelling reason for doing so. Conventionally, these include metabolic rate, and energetic or dietary requirements. Developing solutions to overcome these constraints are necessary, but not sufficient, explanations for the evolution of large brains.
