Joanna Masel
@joannamasel.bsky.social
Theoretical biologist and advisor to data scientists at the University of Arizona. Mostly theoretical population genetics and molecular evolution, but I've also published in biochemistry, infectious disease, aging, economics, education. Opinions are my own
The same difference in exploitative ability yields more coexistence when created by search speed differences than via handling times. 7/9
September 16, 2025 at 5:36 PM
The same difference in exploitative ability yields more coexistence when created by search speed differences than via handling times. 7/9
Other parameters yield the “dominance-discovery” trade-off described in ants, where the Dove loses at contests but is better at finding new resources. We also find a new “Dove-discovery” trade-off, where Hawks search better, but the opportunity costs from contests is too high. 5/9
September 16, 2025 at 5:35 PM
Other parameters yield the “dominance-discovery” trade-off described in ants, where the Dove loses at contests but is better at finding new resources. We also find a new “Dove-discovery” trade-off, where Hawks search better, but the opportunity costs from contests is too high. 5/9
We develop a mechanistic model in which consuming a resource takes time, and Handlers can be interrupted by Searchers who find them rather than free Resource. This initiates a Contest, distracting the consumers, thus allowing the resource to grow to higher levels. 3/9
September 16, 2025 at 5:34 PM
We develop a mechanistic model in which consuming a resource takes time, and Handlers can be interrupted by Searchers who find them rather than free Resource. This initiates a Contest, distracting the consumers, thus allowing the resource to grow to higher levels. 3/9
We applied these concepts to experimental data on 517 Arabidopsis genotypes. The proportion of deaths that were selective is higher than anyone anticipated. Despite artificial conditions, this demonstrates that these concepts can be applied to data – immediately producing a surprise. 13/14
March 19, 2025 at 11:04 PM
We applied these concepts to experimental data on 517 Arabidopsis genotypes. The proportion of deaths that were selective is higher than anyone anticipated. Despite artificial conditions, this demonstrates that these concepts can be applied to data – immediately producing a surprise. 13/14
In a relative fitness model with selection on just one life history stage, selective deaths maps to the lead, illustrated here for the asexual case of Desai & Fisher with the lead q mutations better than the mean, each of them with selection coefficient s academic.oup.com/genetics/art... 9/14
March 19, 2025 at 11:03 PM
In a relative fitness model with selection on just one life history stage, selective deaths maps to the lead, illustrated here for the asexual case of Desai & Fisher with the lead q mutations better than the mean, each of them with selection coefficient s academic.oup.com/genetics/art... 9/14
Lag load arguments are flawed, but in 1971 Nei pmc.ncbi.nlm.nih.gov/articles/PMC... and Felsenstein www.journals.uchicago.edu/doi/10.1086/... derived selective deaths without them. Reproductive excess is a budget out of which selective deaths must be paid. Little work after that 7/14
March 19, 2025 at 11:01 PM
Lag load arguments are flawed, but in 1971 Nei pmc.ncbi.nlm.nih.gov/articles/PMC... and Felsenstein www.journals.uchicago.edu/doi/10.1086/... derived selective deaths without them. Reproductive excess is a budget out of which selective deaths must be paid. Little work after that 7/14
Relative load has since been rediscovered as the "lead" q in traveling wave models. Load/lead is a difference in fitness – this leads to different mathematical insights than approaches based on variances. 5/14
March 19, 2025 at 11:01 PM
Relative load has since been rediscovered as the "lead" q in traveling wave models. Load/lead is a difference in fitness – this leads to different mathematical insights than approaches based on variances. 5/14
Haldane defined "selective deaths" (incl. missing births) as those causally responsible for allele frequency change. The "cost of selection" is the proportion of deaths that need to be selective for a given rate of sweeps.
link.springer.com/article/10.1... 2/14
link.springer.com/article/10.1... 2/14
March 19, 2025 at 10:59 PM
Haldane defined "selective deaths" (incl. missing births) as those causally responsible for allele frequency change. The "cost of selection" is the proportion of deaths that need to be selective for a given rate of sweeps.
link.springer.com/article/10.1... 2/14
link.springer.com/article/10.1... 2/14
How? I have tried several times but the red "deactivate" box can't be clicked on.
March 5, 2025 at 7:07 PM
How? I have tried several times but the red "deactivate" box can't be clicked on.
So I'm still stuck, my 2021 password either doesn't work or I can't find it, and no option to reset.
February 19, 2025 at 1:10 AM
So I'm still stuck, my 2021 password either doesn't work or I can't find it, and no option to reset.
Anyone else unable to log in to NSF via research.gov to access assigned reviews? After completing login.gov 2-factor authentication, I get this screen. I tried to add a yubikey and it doesn't work. I'm just a reviewer, not a government employee!
February 19, 2025 at 12:54 AM
Anyone else unable to log in to NSF via research.gov to access assigned reviews? After completing login.gov 2-factor authentication, I get this screen. I tried to add a yubikey and it doesn't work. I'm just a reviewer, not a government employee!
I'm going to a demonstration today - my first ever. Neighbors helped me make a sign, given my lack of artistic talent or supplies. 2/3
February 17, 2025 at 4:27 PM
I'm going to a demonstration today - my first ever. Neighbors helped me make a sign, given my lack of artistic talent or supplies. 2/3
Whoops! Here is the text, both as snapshot and as alt-text.
February 15, 2025 at 3:38 PM
Whoops! Here is the text, both as snapshot and as alt-text.
Mass testing could beat a range of pathogens if population adherence were high. Frequent testing with rapid test turnaround is more important for diseases that reach peak viral load quickly, eg influenza. 5/9
February 7, 2025 at 10:45 PM
Mass testing could beat a range of pathogens if population adherence were high. Frequent testing with rapid test turnaround is more important for diseases that reach peak viral load quickly, eg influenza. 5/9
Shown here for ancestral SARS-CoV-2, mass testing effectiveness compares well to far more disruptive closures. Effectiveness is proportional to adherence & saturates with frequent testing. 4/9
February 7, 2025 at 10:44 PM
Shown here for ancestral SARS-CoV-2, mass testing effectiveness compares well to far more disruptive closures. Effectiveness is proportional to adherence & saturates with frequent testing. 4/9
Rapid antigen tests take time to develop, so early response needs to do rapid PCR testing at scale. Testing frequently enough, with faster enough test turnaround, makes the limiting factor adherence. 3/9
February 7, 2025 at 10:43 PM
Rapid antigen tests take time to develop, so early response needs to do rapid PCR testing at scale. Testing frequently enough, with faster enough test turnaround, makes the limiting factor adherence. 3/9
We had previously found an exceptionally long-term trend: older animal domains have their hydrophobic amino acids more interspersed along the primary sequence elifesciences.org/articles/57347, driven by differential loss rates. We confirmed that this trend goes all the way back to LUCA. 14/15
December 12, 2024 at 3:53 PM
We had previously found an exceptionally long-term trend: older animal domains have their hydrophobic amino acids more interspersed along the primary sequence elifesciences.org/articles/57347, driven by differential loss rates. We confirmed that this trend goes all the way back to LUCA. 14/15
Our annotations of LUCA’s domains agree well with recent annotation of LUCA’s full-length genes by @emoody.bsky.social @phil-donoghue.bsky.social. doi.org/10.1038/s415... Recent gene-tree species-tree reconciliation methods are what made inferring LUCA possible for both groups. 13/15
December 12, 2024 at 3:52 PM
Our annotations of LUCA’s domains agree well with recent annotation of LUCA’s full-length genes by @emoody.bsky.social @phil-donoghue.bsky.social. doi.org/10.1038/s415... Recent gene-tree species-tree reconciliation methods are what made inferring LUCA possible for both groups. 13/15
Even more ancient “pre-LUCA” protein clans that had diversified pre-LUCA are more enriched for all four aromatic (ring-containing) amino acids than single-copy LUCA-clans. Abiotically produced aromatic amino acids have been found in hydrothermal vents doi.org/10.1038/s415... 11/15
December 12, 2024 at 3:50 PM
Even more ancient “pre-LUCA” protein clans that had diversified pre-LUCA are more enriched for all four aromatic (ring-containing) amino acids than single-copy LUCA-clans. Abiotically produced aromatic amino acids have been found in hydrothermal vents doi.org/10.1038/s415... 11/15
Histidine and cysteine bind the transition metals critical to catalysis -– it makes sense that they came early. Histidine is the most commonly conserved residue in the active site of enzymes, and class 1 synthetases (basic building blocks of the code) have a HIGH motif. 9/15
December 12, 2024 at 3:49 PM
Histidine and cysteine bind the transition metals critical to catalysis -– it makes sense that they came early. Histidine is the most commonly conserved residue in the active site of enzymes, and class 1 synthetases (basic building blocks of the code) have a HIGH motif. 9/15
Early enrichment for cysteine and methionine is compatible with life in a sulfur-rich environment. The two sulfur-containing amino acids are used more by contemporary organisms living in sulfur-rich environments. 8/15
December 12, 2024 at 3:48 PM
Early enrichment for cysteine and methionine is compatible with life in a sulfur-rich environment. The two sulfur-containing amino acids are used more by contemporary organisms living in sulfur-rich environments. 8/15
Histidine was presumed late because it isn’t abiotically available. But the code evolved in a cell capable of ribosomes, not directly from the prebiotic soup. Histidine resembles a purine, and could have been biotically available. journals.plos.org/plosone/arti... 6/15
December 12, 2024 at 3:47 PM
Histidine was presumed late because it isn’t abiotically available. But the code evolved in a cell capable of ribosomes, not directly from the prebiotic soup. Histidine resembles a purine, and could have been biotically available. journals.plos.org/plosone/arti... 6/15
Amino acid size strongly predicts the order of recruitment. (Trifonov's statistical consensus among 40-60 metrics does worse.) Partial outliers are that methionine, histidine, and isoleucine are earlier than expected, and glutamine is later. 5/15
December 12, 2024 at 3:46 PM
Amino acid size strongly predicts the order of recruitment. (Trifonov's statistical consensus among 40-60 metrics does worse.) Partial outliers are that methionine, histidine, and isoleucine are earlier than expected, and glutamine is later. 5/15
When an amino acid is enriched in LUCA relative to ancient but post-LUCA, we deem it early. Trifonov previously classified cysteine and methionine as late because of abiotic unavailability – but of course they weren’t produced in the Miller-Urey experiment, because it added no sulfur! 4/15
December 12, 2024 at 3:45 PM
When an amino acid is enriched in LUCA relative to ancient but post-LUCA, we deem it early. Trifonov previously classified cysteine and methionine as late because of abiotic unavailability – but of course they weren’t produced in the Miller-Urey experiment, because it added no sulfur! 4/15
Not all protein clans go back to the primordial soup. We compared the oldest clans that had diversified prior to LUCA vs. clans descended from just one LUCA copy vs. younger but still-ancient clans not in LUCA but appearing before the last archaeal or bacterial common ancestor. 3/15
December 12, 2024 at 3:45 PM
Not all protein clans go back to the primordial soup. We compared the oldest clans that had diversified prior to LUCA vs. clans descended from just one LUCA copy vs. younger but still-ancient clans not in LUCA but appearing before the last archaeal or bacterial common ancestor. 3/15