In respose to a question posed by me, concerning Tiger Shark teeth, Richard wrote:

. . . regarding possible evolutionary lineages for Galeocerdo cuvier, . . . I don't have any strong feelings about this one but . . .

The scenario G. latidens -> G. mayumbensis -> G. cuvier works from at least several perspectives.

• First, the time frames are OK: G. latidens (AGASSIZ, 1843) is an Eocene species, G. mayumbensis (DARTEVELLE & CASIER, 1943) is Oligocene - Miocene, and G. cuvier (PERON & LESUEUR, 1822) is Miocene - present.
• Secondly, there is a gradual increase in tooth size, with a typical G. latidens anterior tooth being perhaps 2/3 the size of G. cuvier and G. mayumbensis somewhere between the others.
• Thirdly, there is a gradual change in the inclination of the distal cutting edge of the tooth (see photo). In G. latidens, this is sharply inclined toward the point of the main cusp. In G. mayumbensis it is less inclined and in G. cuvier less yet, in fact, it it now almost horizontal.
• Finally, there seems to be a gradual increase in the complexity of serrations. In G. latidens the serrations are simple, while in G. mayumbensis and cuvier the serrations are complex, with serrations having serrations, but G. mayumbensis seems to have simpler serrations than cuvier.

from left to right, lateral teeth from Galeocerdo latidens, G. mayumbensis and G. cuvier

I don't know where G. aduncas (AGASSIZ, 1843) fits into this. There is a small Eocene tiger shark that has not been classified (possibly G. alabamensis?) that could be a possible precursor for G. aduncas. It has simple serrations while G. aduncas's are complex, and I know of no Oligocene transition species between the two. Possibly G. mayumbensis had two off-spring, G. aduncas and G. cuvier (a "small-toothed" species and a "large-toothed" species).