Everything is heritable; "Chimpanzee Intelligence Is Heritable", Hopkins et al 2014 https://pdf.yt/d/0MSB48zQSooDz5Zw / https://www.dropbox.com/s/7dd92ibpg4bgeye/2014-hopkins.pdf ; excerpts:
"Specifically, aside from early attempts to selectively breed for learning skills in rodents [10–12], studies examining the role that genetic factors might play in individual variation in cognitive abilities in nonhuman animals, particularly nonhuman primates, are scarce. Here, we utilized a modified Primate Cognitive Test Battery [13] in conjunction with quantitative genetic analyses to examine whether cognitive performance is heritable in chimpanzees. We found that some but not all cognitive traits were sig- nificantly heritable in chimpanzees. We further found sig- nificant genetic correlations between different dimensions of cognitive functioning, suggesting that the genes that explain the variability of one cognitive trait might also explain that of other cognitive traits.
Cognitive performance was assessed on 13 tasks from the Primate Cognition Test Battery (PCTB) task originally developed by Herrmann and colleagues [13, 14]. The 13 tasks are designed to assess a variety of cognitive abilities, broadly defined as nonsocial and social cognition. To assess the structure and heritability in cognitive performance in the chimpanzees, we performed principal-component analysis (PCA) on their accuracy for individual PCTB tasks. PCA allowed us to derive unbiased component-performance constructs based on item loadings of the different tasks...We also computed a single measure of cognitive performance by deriving a composite factor score from the first unrotated component from a separate PCA analysis (this measure is referred to as the ‘‘g’’ factor). Descriptive data and heritability analyses of the raw performance data can be found in Table S1 and Figure S1.
The PCA with varimax rotation revealed four components with eigenvalues >1.0, and these accounted for 54.20 percent of variance (Table 1). Performance on the tasks involving spatial memory, object permanence, rotation, and transposition loaded on component 1. The causality-visual task and tool use loaded on component 2, while communication production, attention state, and gaze following loaded on component 3. Finally, causality-noise was the single task to load on component 4. Each of the four significant component scores was saved, and we compared these scores between sexes and rearing groups by using multivariate analysis of variance (MANOVA). No significant main effects or interactions were found between sex and rearing conditions on the component scores (Table S1).
As has been done in previous studies in primates [15, 16], we used the program SOLAR (Sequential Oligogenic Linkage Analysis Routines) to estimate heritability [17]. The overall ‘‘g’’ factor score as well the scores for each of the four components derived from the PCA served as the variables of interest in the heritability analyses. Age, sex and rearing history served as covariates. Significant heritability was found for the overall ‘‘g’’ factor score as well as components 1 and 3 but not 2 and 4 (see Figure 1)...None of the covariates accounted for a significant proportion of variance in the PCA components.
Nonetheless, we do believe the findings presented here are stable and valid. For instance, over a two-year period, we re-tested 86 of the original 99 chimpanzees in this study on the 13 PCTB tasks. For the most part, performance was stable over time, although the chimpanzees did significantly better on the retest of the object permanence, rotation, transposition, and relative number tasks, whereas performance was significantly lower for gaze following (Table S2). A PCA on the retest data constrained the number of components to four and revealed a pattern of item loadings similar to that found in the original analysis (Table S3). The only differences in the item loadings for the components between tests were that gaze following loaded on component 4 instead of 3 and the visual-causality task failed to load on any component. Importantly, heritability for the ‘‘g’’ factor based on the retest data was significant (h^2 = 0.624, SE = 0.242, p < 0.005) and quite similar to the values from the original analysis (see Figure 1). Thus, within our sample, the structure and heritability in cognitive performance was consistent over time." #psychology #intelligence #genetics
"Specifically, aside from early attempts to selectively breed for learning skills in rodents [10–12], studies examining the role that genetic factors might play in individual variation in cognitive abilities in nonhuman animals, particularly nonhuman primates, are scarce. Here, we utilized a modified Primate Cognitive Test Battery [13] in conjunction with quantitative genetic analyses to examine whether cognitive performance is heritable in chimpanzees. We found that some but not all cognitive traits were sig- nificantly heritable in chimpanzees. We further found sig- nificant genetic correlations between different dimensions of cognitive functioning, suggesting that the genes that explain the variability of one cognitive trait might also explain that of other cognitive traits.
Cognitive performance was assessed on 13 tasks from the Primate Cognition Test Battery (PCTB) task originally developed by Herrmann and colleagues [13, 14]. The 13 tasks are designed to assess a variety of cognitive abilities, broadly defined as nonsocial and social cognition. To assess the structure and heritability in cognitive performance in the chimpanzees, we performed principal-component analysis (PCA) on their accuracy for individual PCTB tasks. PCA allowed us to derive unbiased component-performance constructs based on item loadings of the different tasks...We also computed a single measure of cognitive performance by deriving a composite factor score from the first unrotated component from a separate PCA analysis (this measure is referred to as the ‘‘g’’ factor). Descriptive data and heritability analyses of the raw performance data can be found in Table S1 and Figure S1.
The PCA with varimax rotation revealed four components with eigenvalues >1.0, and these accounted for 54.20 percent of variance (Table 1). Performance on the tasks involving spatial memory, object permanence, rotation, and transposition loaded on component 1. The causality-visual task and tool use loaded on component 2, while communication production, attention state, and gaze following loaded on component 3. Finally, causality-noise was the single task to load on component 4. Each of the four significant component scores was saved, and we compared these scores between sexes and rearing groups by using multivariate analysis of variance (MANOVA). No significant main effects or interactions were found between sex and rearing conditions on the component scores (Table S1).
As has been done in previous studies in primates [15, 16], we used the program SOLAR (Sequential Oligogenic Linkage Analysis Routines) to estimate heritability [17]. The overall ‘‘g’’ factor score as well the scores for each of the four components derived from the PCA served as the variables of interest in the heritability analyses. Age, sex and rearing history served as covariates. Significant heritability was found for the overall ‘‘g’’ factor score as well as components 1 and 3 but not 2 and 4 (see Figure 1)...None of the covariates accounted for a significant proportion of variance in the PCA components.
Nonetheless, we do believe the findings presented here are stable and valid. For instance, over a two-year period, we re-tested 86 of the original 99 chimpanzees in this study on the 13 PCTB tasks. For the most part, performance was stable over time, although the chimpanzees did significantly better on the retest of the object permanence, rotation, transposition, and relative number tasks, whereas performance was significantly lower for gaze following (Table S2). A PCA on the retest data constrained the number of components to four and revealed a pattern of item loadings similar to that found in the original analysis (Table S3). The only differences in the item loadings for the components between tests were that gaze following loaded on component 4 instead of 3 and the visual-causality task failed to load on any component. Importantly, heritability for the ‘‘g’’ factor based on the retest data was significant (h^2 = 0.624, SE = 0.242, p < 0.005) and quite similar to the values from the original analysis (see Figure 1). Thus, within our sample, the structure and heritability in cognitive performance was consistent over time." #psychology #intelligence #genetics
How do we know?
There is no such thing as intelligene /sarcJul 12, 2014
Jul 12, 2014
