TY - JOUR
T1 - Variation in brain morphology of intertidal gobies
T2 - A comparison of methodologies used to quantitatively assess brain volumes in fish
AU - White, Gemma E.
AU - Brown, Culum
PY - 2015/8/13
Y1 - 2015/8/13
N2 - When correlating brain size and structure with behavioural and environmental characteristics, a range of techniques can be utilised. This study used gobiid fishes to quantitatively compare brain volumes obtained via three different methods; these included the commonly used techniques of histology and approximating brain volume to an idealised ellipsoid, and the recently established technique of X-ray micro-computed tomography (micro-CT). It was found that all three methods differed significantly from one another in their volume estimates for most brain lobes. The ellipsoid method was prone to over- or under-estimation of lobe size, histology caused shrinkage in the telencephalon, and although micro-CT methods generated the most reliable results, they were also the most expensive. Despite these differences, all methods depicted quantitatively similar relationships among the four different species for each brain lobe. Thus, all methods support the same conclusions that fishes inhabiting rock pool and sandy habitats have different patterns of brain organisation. In particular, fishes from spatially complex rock pool habitats were found to have larger telencephalons, while those from simple homogenous sandy shores had a larger optic tectum. Where possible we recommend that micro-CT be used in brain volume analyses, as it allows for measurements without destruction of the brain and fast identification and quantification of individual brain lobes, and minimises many of the biases resulting from the histology and ellipsoid methods.
AB - When correlating brain size and structure with behavioural and environmental characteristics, a range of techniques can be utilised. This study used gobiid fishes to quantitatively compare brain volumes obtained via three different methods; these included the commonly used techniques of histology and approximating brain volume to an idealised ellipsoid, and the recently established technique of X-ray micro-computed tomography (micro-CT). It was found that all three methods differed significantly from one another in their volume estimates for most brain lobes. The ellipsoid method was prone to over- or under-estimation of lobe size, histology caused shrinkage in the telencephalon, and although micro-CT methods generated the most reliable results, they were also the most expensive. Despite these differences, all methods depicted quantitatively similar relationships among the four different species for each brain lobe. Thus, all methods support the same conclusions that fishes inhabiting rock pool and sandy habitats have different patterns of brain organisation. In particular, fishes from spatially complex rock pool habitats were found to have larger telencephalons, while those from simple homogenous sandy shores had a larger optic tectum. Where possible we recommend that micro-CT be used in brain volume analyses, as it allows for measurements without destruction of the brain and fast identification and quantification of individual brain lobes, and minimises many of the biases resulting from the histology and ellipsoid methods.
KW - Brain morphology
KW - Ellipsoid model
KW - Histology
KW - Intertidal gobies
KW - Micro-computed tomography
KW - Neuroecology
UR - http://www.scopus.com/inward/record.url?scp=84942195817&partnerID=8YFLogxK
U2 - 10.1159/000398781
DO - 10.1159/000398781
M3 - Article
C2 - 26183604
AN - SCOPUS:84942195817
SN - 0006-8977
VL - 85
SP - 245
EP - 256
JO - Brain, Behavior and Evolution
JF - Brain, Behavior and Evolution
IS - 4
ER -