The researchersfurthernote: "There is evidence of hybridization across species (such as between spotted and harbor seals) as well as across genera (such as hard and hoodedseals)."
You might furthernote and recall from the above Funds From Operations and price correlated graph this was also a time when the price was touching the pink income valuation line.
Further, note that over variable time scales Simon is still correct: it really is true that new technologies of extraction are developed and these increase supply and push prices down.