“ The developmental primordium that produces the premaxilla in nonmammalian tetrapods rarely contributes to the upper jaw in therian mammals but rather forms a motile nose. We propose that these previously unrecognized rearrangements allowed key innovations such as the highly sensitive tactile perception and olfactory function in mammalian evolution.”
It never occurred to me before that mammals, or specifically the placental and marsupial subset, had the most developed olfactory sense. Perhaps then a sense of smell is more complex to develop, in evolutionary terms, than sight or hearing? A strange idea indeed since sight is typically considered the most sophisticated sense.
Smell is more complicated in a straight-forward way. Each distinct chemical sensor needs its own genetic coding, while eyes get by with a handful of distinct sensors, repeated spatially. Spatial patterns don’t need much coding.
Sense of smell is fascinating. I remember reading that there are dozens (hundreds?) of these distinct receptors and each has a different response curve for a given substance. So you end up with a huge multi dimensional space, which explains why there are so many unique smells.
The For Whom the Bell Tolls quote is a striking way to start the introduction. It makes the point of their inquiry much more obvious than the formal scientific language that follows. I'd love to see more of this ("real-world" connections, not movie quotes) in scientific writing.
It never occurred to me before that mammals, or specifically the placental and marsupial subset, had the most developed olfactory sense. Perhaps then a sense of smell is more complex to develop, in evolutionary terms, than sight or hearing? A strange idea indeed since sight is typically considered the most sophisticated sense.