Walid Mawass
@wmawass.bsky.social
Evolutionary geneticist. I think about evolution across timescales and constraints on it from interactions at each scale. I use both population and quantitative genetics to do science. I love music, writing, and my cats (order varies on a daily basis).
Bottom line: detecting consistent selection and additive genetic variance does not guarantee an evolutionary response.
Our study highlights how even with selection + heritability, evolutionary stasis can persist.
🧬 Evolution isn’t always as predictable as we think!
Preprint: tinyurl.com/mr3r5vk3
Our study highlights how even with selection + heritability, evolutionary stasis can persist.
🧬 Evolution isn’t always as predictable as we think!
Preprint: tinyurl.com/mr3r5vk3
Contrasting evolutionary outcomes in a human life history trait which is heritable and under consistent unbiased directional selection
Microevolution is well documented in natural populations, yet its persistence as an adaptive process remains debated. Despite widespread directional selection on heritable traits, including life-histo...
tinyurl.com
October 15, 2025 at 2:43 PM
Bottom line: detecting consistent selection and additive genetic variance does not guarantee an evolutionary response.
Our study highlights how even with selection + heritability, evolutionary stasis can persist.
🧬 Evolution isn’t always as predictable as we think!
Preprint: tinyurl.com/mr3r5vk3
Our study highlights how even with selection + heritability, evolutionary stasis can persist.
🧬 Evolution isn’t always as predictable as we think!
Preprint: tinyurl.com/mr3r5vk3
Why? Several possibilities:
– Not enough time (7 generations)
– Small population size → drift
– G×E interactions constraining response
– Hidden life-history trade-offs limiting evolution
– Not enough time (7 generations)
– Small population size → drift
– G×E interactions constraining response
– Hidden life-history trade-offs limiting evolution
October 15, 2025 at 2:43 PM
Why? Several possibilities:
– Not enough time (7 generations)
– Small population size → drift
– G×E interactions constraining response
– Hidden life-history trade-offs limiting evolution
– Not enough time (7 generations)
– Small population size → drift
– G×E interactions constraining response
– Hidden life-history trade-offs limiting evolution
So what’s going on?
We see clear selection on a heritable trait, yet no evolutionary response.
This suggests that contemporary microevolutionary change is inconsistent and unpredictable — even under strong selection.
We see clear selection on a heritable trait, yet no evolutionary response.
This suggests that contemporary microevolutionary change is inconsistent and unpredictable — even under strong selection.
October 15, 2025 at 2:43 PM
So what’s going on?
We see clear selection on a heritable trait, yet no evolutionary response.
This suggests that contemporary microevolutionary change is inconsistent and unpredictable — even under strong selection.
We see clear selection on a heritable trait, yet no evolutionary response.
This suggests that contemporary microevolutionary change is inconsistent and unpredictable — even under strong selection.
Using the Breeder’s Equation and the Robertson–Price covariance, we predicted evolutionary responses.
Only in Charlevoix did both models predict a strong response… that never happened.
In short: selection ≠ evolution, even when theory says it should.
Only in Charlevoix did both models predict a strong response… that never happened.
In short: selection ≠ evolution, even when theory says it should.
October 15, 2025 at 2:43 PM
Using the Breeder’s Equation and the Robertson–Price covariance, we predicted evolutionary responses.
Only in Charlevoix did both models predict a strong response… that never happened.
In short: selection ≠ evolution, even when theory says it should.
Only in Charlevoix did both models predict a strong response… that never happened.
In short: selection ≠ evolution, even when theory says it should.
Across cohorts, mean AFR changed differently across populations.
And when we looked at breeding values, there was no consistent genetic trend either.
(See figure — phenotypic vs. genetic patterns across time.)
And when we looked at breeding values, there was no consistent genetic trend either.
(See figure — phenotypic vs. genetic patterns across time.)
October 15, 2025 at 2:43 PM
Across cohorts, mean AFR changed differently across populations.
And when we looked at breeding values, there was no consistent genetic trend either.
(See figure — phenotypic vs. genetic patterns across time.)
And when we looked at breeding values, there was no consistent genetic trend either.
(See figure — phenotypic vs. genetic patterns across time.)
Our focal trait: age at first reproduction (AFR).
Linear models show strong directional selection favoring earlier AFR (see figure 👇).
Quantitative genetic models confirm that AFR is heritable (h² ≈ 0.11).
Yet—things get interesting.
Linear models show strong directional selection favoring earlier AFR (see figure 👇).
Quantitative genetic models confirm that AFR is heritable (h² ≈ 0.11).
Yet—things get interesting.
October 15, 2025 at 2:43 PM
Our focal trait: age at first reproduction (AFR).
Linear models show strong directional selection favoring earlier AFR (see figure 👇).
Quantitative genetic models confirm that AFR is heritable (h² ≈ 0.11).
Yet—things get interesting.
Linear models show strong directional selection favoring earlier AFR (see figure 👇).
Quantitative genetic models confirm that AFR is heritable (h² ≈ 0.11).
Yet—things get interesting.
We identified three subpopulations that can be considered semi-independent replicates: they share genetic and historical backgrounds and similar demographic histories as early French settlers spread across Québec.
(These pedigrees were validated in our earlier QG analyses.)
(These pedigrees were validated in our earlier QG analyses.)
October 15, 2025 at 2:43 PM
We identified three subpopulations that can be considered semi-independent replicates: they share genetic and historical backgrounds and similar demographic histories as early French settlers spread across Québec.
(These pedigrees were validated in our earlier QG analyses.)
(These pedigrees were validated in our earlier QG analyses.)
To tackle this, we needed longitudinal data with pedigree info to track phenotypic and genetic changes over time — in other words, replicated populations where quantitative genetic models are possible.
The historical French-Canadian (Québec) population turned out to be the perfect system.
The historical French-Canadian (Québec) population turned out to be the perfect system.
October 15, 2025 at 2:43 PM
To tackle this, we needed longitudinal data with pedigree info to track phenotypic and genetic changes over time — in other words, replicated populations where quantitative genetic models are possible.
The historical French-Canadian (Québec) population turned out to be the perfect system.
The historical French-Canadian (Québec) population turned out to be the perfect system.
One of my favorite posters among those I visited yesterday! Awesome graphics and color palette.
June 24, 2025 at 8:57 PM
One of my favorite posters among those I visited yesterday! Awesome graphics and color palette.