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Biology of Sea Turtles, Vol. II
(Figure 2.28). Among the cheloniids, the brain is closest to the skull roof in L. kempii.
It is farthest from the skull roof in adult C. caretta and E. imbricata (Wyneken,
2001). Scalation patterns on the head and the position of the ear provide speciesspecific landmarks for some structures (Figure 2.28).The leatherback brain is housed
deeply, except for the pineal organ, which extends dorsally in a cartilaginous conelike chamber adjacent to the pink spot on the middorsal surface of the head. The
pineal effects pigmentation, responds to photoperiod, and modulates biological
rhythms. It may play a role in regulating reproductive cycles.
FIGURE 2.28 The position of the brain and braincase relative to head landmarks is shown
for five species for which reliable data were available. The species vary in the extent of
dorsoventral torsion and the depth of the brain relative to the roof of the skull. (From Wyneken,
J. The Anatomy of Sea Turtles, U.S. Department of Commerce, NOAA Technical Memorandum NMFS-SEFSC-470, 2001. With permission.)
1123_C02.fm Page 74 Friday, November 15, 2002 11:16 AM
Biology of Sea Turtles, Vol. II
(Figure 2.28). Among the cheloniids, the brain is closest to the skull roof in L. kempii.
It is farthest from the skull roof in adult C. caretta and E. imbricata (Wyneken,
2001). Scalation patterns on the head and the position of the ear provide speciesspecific landmarks for some structures (Figure 2.28).The leatherback brain is housed
deeply, except for the pineal organ, which extends dorsally in a cartilaginous conelike chamber adjacent to the pink spot on the middorsal surface of the head. The
pineal effects pigmentation, responds to photoperiod, and modulates biological
rhythms. It may play a role in regulating reproductive cycles.
FIGURE 2.28 The position of the brain and braincase relative to head landmarks is shown
for five species for which reliable data were available. The species vary in the extent of
dorsoventral torsion and the depth of the brain relative to the roof of the skull. (From Wyneken,
J. The Anatomy of Sea Turtles, U.S. Department of Commerce, NOAA Technical Memorandum NMFS-SEFSC-470, 2001. With permission.)
1123_C02.fm Page 74 Friday, November 15, 2002 11:16 AM