DOI: 10.5061/dryad.h9w0vt4nv
title: The evolution of plasticity in brain morphology following colonization of an ecologically divergent habitat in Trinidadian guppies

description: Natural environments are constantly changing. To survive, organisms will
 either need to rapidly adapt to new conditions or colonize new habitats.
 Colonization has been hypothesized to select for increased plasticity as
 well as increased brain size, though empirical tests of these effects have
 proven difficult to evaluate. In particular, the degree to which
 plasticity of brain morphology can evolve, and its subsequent ecological
 consequences have rarely been explored. Trinidadian guppies (Poecilia
 reticulata) are known for their repeated adaptation to ancestral
 high-predation (HP) and derived low-predation (LP) environments. We used
 this system to examine the evolution and plasticity of brain morphology.
 We exposed second-generation offspring of individuals collected from HP
 and LP sites to two different kinds of environmental treatments: predation
 cues and conspecific social environment. We found that guppies descended
 from a colonized LP habitat showed greater plasticity in brain morphology
 than descendants of their ancestral HP population, supporting the
 hypothesis that plasticity of brain morphology may increase fitness after
 colonization of a novel habitat. Additionally, we show sexual dimorphism
 in brain morphology plasticity. Overall, these results suggest the
 evolution of brain morphology plasticity as an important mechanism that
 allows for ecological diversification and colonization of novel habitats.
description: Data aquired via analysis of brain region volumes and brain mass
 of Trinidadian guppies raised in a plasticity experiment. 
description: The evolution of plasticity in brain morphology following colonization of
 an ecologically divergent habitat in Trinidadian guppies: Data
 description. This data describes results of a plasticity experiment
 testing development of brain form across high and low predation source
 populations of Trinidadian guppies as well as plasticity treatments.
 **ID:** Non informative identification **IDD:** Informative identification
 **Family: **Mother identification **Sex** **            M:** male, **F:**
 female **Source: **Source population from which wild individuals were
 captured that were then reproduced to form F2 offspring used in the
 experiment.             **LP:** low-predation, **HP:** high-predation
 **Pred: **Experimental predator treatment.             **C:** reared in
 the absence of predator cues, **P:** reared in the presence of predator
 cues. **Group: **Experimental sociality treatment.             **Solo**:
 reared alone, **Same: **reared in the presence of conspecifics from the
 same source population, **Diff: **reared in the presence of conspecifics
 from the other source population. **BM:** Brain mass, measured in grams.
 **Cb: **Cerebellum volume, measured in cubic millimeters. **OT:** Optic
 tectum volume, measured in cubic millimeters. **Tel:** Telencephalon
 volume, measured in cubic millimeters. **OB:** Olfactory bulb volume,
 measured in cubic millimeters. **Hyp:** Hypothalamus volume, measured in
 cubic millimeters. **Length: **Standard length, measured in millimeters.
 **GL: **Oral jaw width, measured in millimeters. **Age: **Measured in
 days. \**Mass: **Total body mass, measured in grams.