Covarying Shell Growth Parameters and the Regulation of Shell Shape in Marine Bivalves: A Case Study on Tellinoidea

Table 2

The relative variations (𝜕𝐸/𝐸)/(𝜕𝛼/𝛼), (𝜕𝐸/𝐸)/(𝜕𝜌/𝜌), (𝜕𝐸/𝐸)/(𝜕𝛿/𝛿), (𝜕𝐷/𝐷)/(𝜕𝛼/𝛼), (𝜕𝐷/𝐷)/(𝜕𝜌/𝜌), (𝜕𝐷/𝐷)/(𝜕𝛿/𝛿), (𝜕𝐾/𝐾)/(𝜕𝛼/𝛼), (𝜕𝐾/𝐾)/(𝜕𝜌/𝜌), and (𝜕𝐾/𝐾)/(𝜕𝛿/𝛿) of the functionally relevant parameters 𝐸, 𝐷, 𝐾, according to variations of the growth-based parameters 𝛼, 𝜌, 𝛿.

(a) for the genus Donax

	𝜕𝐸/𝐸	𝜕𝐷/𝐷	𝜕𝐾/𝐾
𝜕𝛼/𝛼	+0.72	−0.73	+1.80
𝜕𝜌/𝜌	−0.99	0.00	+1.72
𝜕𝛿/𝛿	+0.35	+1.60	−0.18

(b) for the genus Tellina

	𝜕𝐸/𝐸	𝜕𝐷/𝐷	𝜕𝐾/𝐾
𝜕𝛼/𝛼	+0.65	−0.23	+1.87
𝜕𝜌/𝜌	−0.98	0.00	+1.35
𝜕𝛿/𝛿	+0.13	+1.46	−0.08