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Posts by Bryan Gitschlag

Mary Jane van der Pot 🫩

2 weeks ago 1 0 1 0
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two men standing next to each other with the words i 'm writing this down this is good stuff on the bottom Alt: Scene from Back to the Future, in which a teenage George McFly is receiving dating advice from his teenage son (from the future), while saying "I'm writing this down. This is good stuff."
3 weeks ago 0 0 0 0

I grew tomatoes in grad school. They attracted caterpillars. The caterpillars became parasitized by wasps. I learned from my committee chair @symbionticism.bsky.social that parasitic wasps frequently have parasitic bacterial endosymbionts, which have their own viruses...

#ParasitesAllTheWayDown

3 weeks ago 3 2 3 0

I grew tomatoes in grad school. They attracted caterpillars. The caterpillars became parasitized by wasps. I learned from my committee chair @symbionticism.bsky.social that parasitic wasps frequently have parasitic bacterial endosymbionts, which have their own viruses...

#ParasitesAllTheWayDown

3 weeks ago 3 2 3 0

It’s possible to love stained glass windows and pipe organs and still call out misogyny and transphobia.

4 weeks ago 16 1 1 0

Oh I’m excited to dig into this! I especially love that figure with the environment & behavioral variables mapped onto the phylogeny! In my grad work, I found that nutrient stress intensifies selection against a selfish mtDNA… can’t help but wonder if it was a molecular case of a similar phenomenon.

2 months ago 2 1 0 0
Highlighted excerpt from Darwin's book On the Origin of Species, which reads: "The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons) extremely uniform, and everything seems simple enough; but when these mongrels are crossed one with another for several generations, hardly two of them will be alike,..."

Highlighted excerpt from Darwin's book On the Origin of Species, which reads: "The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons) extremely uniform, and everything seems simple enough; but when these mongrels are crossed one with another for several generations, hardly two of them will be alike,..."

Highlighted excerpt from Darwin's book On the Origin of Species, which reads: "Thus I believe it has been with social insects: a slight modification of structure, or instinct, correlated with the sterile condition of certain members of the community, has been advantageous to the community: consequently the fertile males and females of the same community flourished, and transmitted to their fertile offspring a tendency to produce sterile members having the same modification."

Highlighted excerpt from Darwin's book On the Origin of Species, which reads: "Thus I believe it has been with social insects: a slight modification of structure, or instinct, correlated with the sterile condition of certain members of the community, has been advantageous to the community: consequently the fertile males and females of the same community flourished, and transmitted to their fertile offspring a tendency to produce sterile members having the same modification."

Some favorite Darwin facts from "On the Origin of Species"…

1. He came this close 🤏 to figuring out Mendelian genetics (if only he had put numbers on those observations!)

2. Proposed the basic idea of Inclusive Fitness Theory, a leading explanation for evolution of animal altruism.

#DarwinDay

2 months ago 1 0 0 0

Faith healers remind me of how martial arts masters are often perceived (by their students) to have superhuman abilities.

Martial arts master George Dillman once famously explained to a Nat Geo filmcrew that his “no touch” knockout didn’t work on a skeptic because the guy was “a total nonbeliever.”

2 months ago 1 0 2 0

I'm sorry to hear about your loss. Sending you virtual hugs. Do you have any particularly favorite memories of him, or your time with him, that you'd be willing to share?

2 months ago 2 0 0 0
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Predation, evo-devo, and historical contingency: A nematode predator drives evolution of aggregative multicellularity Research into the evolution of multicellularity often focuses on clonal multicellularity, yet aggregative multicellularity (AM) may respond to different drivers and is also highly interesting evolutionarily, for example in its behavioral, regulatory, morphological, and social complexity and diversity. We investigate the potential for predation to shape AM evolution across different combinations of three species comprising a multi-trophic food web. Together in a three-species community, the fruiting bacterium Myxococcus xanthus is a mesopredator, while the bacterivorous nematode Pristionchus pacificus is apex predator and the bacterium Escherichia coli is a shared basal prey for both predators. The number and morphology of M. xanthus fruiting bodies is found to respond evolutionarily to nematodes, regardless of whether E. coli is present. E. coli alone with M. xanthus tends to reduce both fruiting body formation and spore production, but adding nematodes eliminates those negative effects. M. xanthus lineages with an ancestral antibiotic-resistance mutation evolved less overall, revealing strong historical contingency and suggesting potential tradeoffs between antibiotic-resistance and responsiveness to biotic selection. Our results suggest that predation both of and by mesopredators has played important roles in the evolution of aggregative multicellularity and reveal complex inter-trophic evolutionary interactions in a relatively simple three-species food web. ### Competing Interest Statement The authors have declared no competing interest. European Molecular Biology Organization, https://ror.org/04wfr2810, ALTF 1208–2017 Swiss National Science Foundation, 31003A_16005, 310030B_182830

Really cool study by @evokait.bsky.social et al.

In a simple three-species food web, presence of an apex predator (nematode) promotes aggregative multicellularity in the predatory bacterium Myxococcus xanthus.

www.biorxiv.org/content/10.1...

2 months ago 1 0 0 0

Oh this ought to be a great talk!

Is there a link to attend? I'm not seeing any way to see the talk on the event webpage.

2 months ago 1 0 1 0

Buddhism?

Also, to be fair, I think you just described a lot of mainline/liberal Protestantism.

3 months ago 1 0 1 0

I doubt that's news but I think it underscores how we're talking about fringe views (which seem to get a disproportionate amount of exposure on social media, unfortunately) rather than something that represents the field as a whole. Evolutionary biologists know sex is complex & can't be pigeonholed.

3 months ago 2 0 1 0

Hi, evolutionary biologist here. To add to what others have said, I just wanna mention that since transphobia & trans-exclusionary views on sex have no basis in evolutionary theory, one possibility is they're just invoking credentials to give the appearance of legitimacy to their prejudices.

3 months ago 2 0 1 0
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a man in a tuxedo sits in a chair in front of a staircase with people walking down it Alt: A man in a tuxedo and top hat sits in a chair in the grand staircase on the titanic watching in horror as the water approaches his feet. People around him are fleeing the rising water.

👀

4 months ago 2 0 0 0

Not only that, but the insinuation that someone shouldn’t receive care for a medical emergency, unless they have a visa or green card, seems kinda sociopathic.

4 months ago 1 0 0 0

Another idea: it’s difficult to get their gene products back into the mitochondria if encoded in the nucleus. The remaining mtDNA proteins are largely hydrophobic, and they can reportedly be mis-targeted to the endoplasmic reticulum when expressed in the nucleus.

(Not an exhaustive list!)

6/6

4 months ago 1 0 0 0

Why are some genes being left behind in the mitochondria? One proposed idea is that it’s easier to couple their expression to energetic feedbacks in a fine-tuned way, if they’re in close physical proximity to the ETC. The proteins encoded in animal mtDNA are considered core ETC components.

5/6

4 months ago 1 0 1 0

And there appear to be mechanisms for such mt-to-nuc migration. Some studies have reported mtDNA sequences that integrated in the nuclear genome, as real-time (e.g. due to aberrant repair of double-strand breaks, either in cancer or as a consequence of attempts to induce breaks for DNA editing)

4/6

4 months ago 1 0 1 0
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One idea I speculated about in my thesis (not aware of data to support it, but makes sense in principle) is that if an mtDNA gene is copied to the nucleus, a mutant mtDNA with a deletion of that gene can ‘selfishly’ rise to high frequency without harming the host, thanks to the nuclear copy.

3/6

4 months ago 1 0 1 0

There are benefits to having mitochondrial genes migrate to the nucleus. For example it puts distance from the source of mutagenic byproducts of OXPHOS. It also makes their inheritance more regulated (mtDNA inheritance is more stochastic & non-Mendelian, prone to selfish genetic elements).

2/6

4 months ago 1 0 1 0

Awesome questions! I was asked some of these in my qualifying exam 😅

To your first question, it’s often more the former, especially for Electron Transport Chain components (some proteins that localize to mitochondria, involving immunity for example, likely had a nuclear origin to my knowledge)

1/6

4 months ago 2 0 1 1

Oh dear. That’s like, “oh you’re a barista? Make me a coffee, hehe.”

4 months ago 2 0 0 0

I do appreciate the question for the opportunity to clarify some misconceptions about how evolution of biological complexity works, but the question is almost never in good faith. Usually more of a ‘gotcha.’

4 months ago 3 0 0 0

Evolutionary biologist. “How do you explain [complex thing]?”

4 months ago 1 0 1 0

Let me know if you start seeing shiny things like buttons and coins lying around your property. :)

6 months ago 1 0 1 0
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What about moderately communist?

6 months ago 1 0 1 0

Evolution 😅

7 months ago 1 0 0 0

Dr. Knurick seems to be most active in the video-based social media platforms like іnstа.

7 months ago 2 0 0 0

Their bsky info…
@drjessicaknurick.bsky.social
@amylnon.bsky.social

7 months ago 1 0 1 0