160
Interesting results have been reported about existence of specifi c area within
trout nose (the region of location of the olfactory lamellae) that contains cells with
magnetite particles. Moreover, it was shown that these magnetite-containing cells
are innervated by the ros V nerve. It cannot be excluded that these cells “function as
magnetoreceptors and relay information to the brain through the trigeminal nerve.
Because reversals of fi eld direction did not elicit responses from units in the ros V
nerve, the putative magnetite receptors have been hypothesized to detect fi eld
intensity, a parameter that is potentially useful in a map sense,” (Lohmann and
Johnsen 2000 ; see also Bohannon 2007 ).
In the chapter above, I reported about the fi nding of magnetite microparticles
within the vestibular apparatus of guitar fi sh (O’Leary et al. 1981 ; Vilches-Troya
et al. 1984 ). Thus, the location place for magnetite in fi sh seems to be different
for different species. For example, magnetite has been located in Sockeye Salmon
( O. nerca ) “near the basal lamina of the olfactory epithelium, the area innervated by
the trigeminal nerve,” (Muheim 2001 ; see for more information Mann et al. 1988 ;
Walker et al. 1988 , 1997 ). Here, some additional locations for SD magnetite
nanoparticles within other fi sh species as follow (Diebel et al. 2000 ):
• dermethmoid cartilage of the skull, Chinook salmon ( O. tshawytscha ), Yellowfi n
Tuna ( Thunnus albacares ) (Walker et al. 1984 ; Kirschvink et al. 1985b );
• the olfactory lamellae in Rainbow Trout ( Oncorhynchus mykiss ) (Walker et al. 1997 ).
Interestingly, the fi sh species Scombridae and Salmonidae are the only examples,
which confi rm direct evidence of SD magnetite in vertebrates (Ueda et al. 1986 ;
Cadiou and McNaughton 2010 ).
3.5.2 Magnetite in Marine Reptiles
Long-distance migrations are impressive and characteristic behavioral features of
most sea turtle species. As reported by Lohmann and Lohmann ( 2006 ), “the journey
that loggerhead turtles ( Caretta caretta ) take from their nesting beaches in Japan to
their feeding areas near Baja California and back is the longest migration known for
a marine animal,” (Lohmann and Lohmann 2006 ). Thus, sea turtles are known to
undergo migrations between nesting beaches and feeding grounds separated in some
cases by thousands of kilometers (Carr 1967 ; Lohmann et al. 1999 ). How such navigation is accomplished has not been determined. By virtue of magnetoreception,
however, turtles could potentially detect several parameters of local magnetic fi elds
that could be used as components of a map sense (Gould 1985 ). Some geomagnetic
parameters, such as fi eld line inclination (dip angle), horizontal fi eld intensity, and
vertical fi eld intensity vary with latitude (Skiles 1985 ). Any of these could be used as
one component of a map for determining location with respect to a goal (e.g. a nesting beach). Turtles might also have the ability to detect and remember para meters of
localized magnetic anomalies unique to specifi c sites such as feeding, mating, or
nesting grounds. It was reported that complete darkness is not a barrier for hatchlings
3 Biocomposites and Mineralized Tissues
Interesting results have been reported about existence of specifi c area within
trout nose (the region of location of the olfactory lamellae) that contains cells with
magnetite particles. Moreover, it was shown that these magnetite-containing cells
are innervated by the ros V nerve. It cannot be excluded that these cells “function as
magnetoreceptors and relay information to the brain through the trigeminal nerve.
Because reversals of fi eld direction did not elicit responses from units in the ros V
nerve, the putative magnetite receptors have been hypothesized to detect fi eld
intensity, a parameter that is potentially useful in a map sense,” (Lohmann and
Johnsen 2000 ; see also Bohannon 2007 ).
In the chapter above, I reported about the fi nding of magnetite microparticles
within the vestibular apparatus of guitar fi sh (O’Leary et al. 1981 ; Vilches-Troya
et al. 1984 ). Thus, the location place for magnetite in fi sh seems to be different
for different species. For example, magnetite has been located in Sockeye Salmon
( O. nerca ) “near the basal lamina of the olfactory epithelium, the area innervated by
the trigeminal nerve,” (Muheim 2001 ; see for more information Mann et al. 1988 ;
Walker et al. 1988 , 1997 ). Here, some additional locations for SD magnetite
nanoparticles within other fi sh species as follow (Diebel et al. 2000 ):
• dermethmoid cartilage of the skull, Chinook salmon ( O. tshawytscha ), Yellowfi n
Tuna ( Thunnus albacares ) (Walker et al. 1984 ; Kirschvink et al. 1985b );
• the olfactory lamellae in Rainbow Trout ( Oncorhynchus mykiss ) (Walker et al. 1997 ).
Interestingly, the fi sh species Scombridae and Salmonidae are the only examples,
which confi rm direct evidence of SD magnetite in vertebrates (Ueda et al. 1986 ;
Cadiou and McNaughton 2010 ).
3.5.2 Magnetite in Marine Reptiles
Long-distance migrations are impressive and characteristic behavioral features of
most sea turtle species. As reported by Lohmann and Lohmann ( 2006 ), “the journey
that loggerhead turtles ( Caretta caretta ) take from their nesting beaches in Japan to
their feeding areas near Baja California and back is the longest migration known for
a marine animal,” (Lohmann and Lohmann 2006 ). Thus, sea turtles are known to
undergo migrations between nesting beaches and feeding grounds separated in some
cases by thousands of kilometers (Carr 1967 ; Lohmann et al. 1999 ). How such navigation is accomplished has not been determined. By virtue of magnetoreception,
however, turtles could potentially detect several parameters of local magnetic fi elds
that could be used as components of a map sense (Gould 1985 ). Some geomagnetic
parameters, such as fi eld line inclination (dip angle), horizontal fi eld intensity, and
vertical fi eld intensity vary with latitude (Skiles 1985 ). Any of these could be used as
one component of a map for determining location with respect to a goal (e.g. a nesting beach). Turtles might also have the ability to detect and remember para meters of
localized magnetic anomalies unique to specifi c sites such as feeding, mating, or
nesting grounds. It was reported that complete darkness is not a barrier for hatchlings
3 Biocomposites and Mineralized Tissues