Sea cucumber poop is surprisingly important for the ecosystem pic.twitter.com/OL33hlAve6— National Geographic (@NatGeo) September 7, 2018
The Tree of Life
Blog of Jonathan A. Eisen, Professor at U.C. Davis.
Friday, September 07, 2018
Today in poop news
Friday, May 18, 2018
Koalas, Chlamydia, Microbiomania, Katie Dahlhausen, John Oliver, Russell Crowe, and me.
I love Chlamydia. Really I do. It was in a paper analyzing two Chlamydial genomes that I first noticed a very strange pattern of genome evolution.

This in turn led to our discovery that large genome inversions in bacteria and archaea are most common when they are symmetric around the origin of replication.

This may be my favorite paper from my entire career and I owe it all to Chlamydia.
Plus, there are all sorts of jokes one can make with the Giant Microbe Chlamydias like

This in turn led to our discovery that large genome inversions in bacteria and archaea are most common when they are symmetric around the origin of replication.

This may be my favorite paper from my entire career and I owe it all to Chlamydia.
Plus, there are all sorts of jokes one can make with the Giant Microbe Chlamydias like
andIronic I know but putting Chlamydia near my special place makes it awkward to go #ucdmicroboome pic.twitter.com/DR8eEJdDOA— Jonathan Eisen (@phylogenomics) October 27, 2017
It reminds me of when we all kept giving each other chlamydia with @phylogenomics 's 'Gut Check' game at #scifoo :D who doesn't love a free set of crabs lol! https://t.co/ltuxAbKFFC— Carin Anne Bondar (@carinbondar) February 14, 2018
Monday, April 30, 2018
No Microbiome Santa Claus we cannot magically convert correlative studies into causal ones. And scientists dishing out medical advice about vaping based on such bad science is ridiculous.
Aaarrrrrrrg. That is how I feel right now.
Many microbiome studies involve examining the microbiome in various samples and asking and answering "Are there differences in the microbiome between my sample types?". This is a standard correlative analysis used in all sorts of areas of science. and it can be quite useful in many cases.
However, in most cases it is not OK to take information from a correlative study and infer that the microbiome was "changed" due to some factor that differed between the samples. Generally this would only be possible to do in some sort of controlled experimental manipulation experiment. But so so so many people make such inferences and I am going to highlight an example that relates to a new study of vaping and the microbiome.
There is a new paper on this topic and an associated press release:
papers vapers). Note - they did not study people before and after vaping or smoking. They compared different people who differed in these behaviors but also differ in 100s to 1000s of other things like diet, gender, age, activity, housing, childhood, and more.
And when they did comparisons in relation to the main variables of non smoker, smoker, vaper, they found some differences in microbiomes and some similarities. Small study. But potentially interesting.
However, the PR significantly misrepresents what they did and found. Here are some examples of wording I have a problem with:
Press Release:
Many microbiome studies involve examining the microbiome in various samples and asking and answering "Are there differences in the microbiome between my sample types?". This is a standard correlative analysis used in all sorts of areas of science. and it can be quite useful in many cases.
However, in most cases it is not OK to take information from a correlative study and infer that the microbiome was "changed" due to some factor that differed between the samples. Generally this would only be possible to do in some sort of controlled experimental manipulation experiment. But so so so many people make such inferences and I am going to highlight an example that relates to a new study of vaping and the microbiome.
There is a new paper on this topic and an associated press release:
- Press Release: Vapers and non-smokers have the same flourishing gut flora | EurekAlert! Science News
- Paper: Effects of tobacco smoke and electronic cigarette vapor exposure on the oral and gut microbiota in humans: a pilot study
And when they did comparisons in relation to the main variables of non smoker, smoker, vaper, they found some differences in microbiomes and some similarities. Small study. But potentially interesting.
However, the PR significantly misrepresents what they did and found. Here are some examples of wording I have a problem with:
Press Release:
- "Vapers and non-smokers have the same flourishing gut flora."
- OK this has nothing to do with the point of my post but they do not in any way show "flourishing" flora.
- "whilst smokers have significant changes to their microbiome".
- No. They show differences. Not changes
- Significant changes were found in the gut bacteria of the smokers, with an increase in the Prevotella bacteria which is linked to an increased risk of colon cancer and colitis.
- Again. No. They show differences. They do not know if they are changes since they do not know what these people had before smoking. And thus they cannot show "increases" either.
- There was also a decrease in the presence of Bacteroides in smokers, a beneficial bacteria or probiotic.
- No - no decrease shown. And for that matter - not all Bacteroides are beneficial or probiotic.
- More investigation is needed but to find that vaping is less-damaging than smoking on our gut bacteria adds to the incentive to change to e-cigarettes and for people to use them as a tool to quit smoking completely.
- Jesus #(@(@. No. They did not show this.
- This revealed significant changes in the gut bacteria of the faecal samples.
- Again, no.
Saturday, April 28, 2018
Excellent podcast on #microbiomania - aka microbiome hype from Health News Review
Really well done Podcast on Microbiome Hype from Health News Review
Podcast: Gut Punch - Marketing Microbiome Hype - HealthNewsReview.org
Definitely worth a listen.
Podcast: Gut Punch - Marketing Microbiome Hype - HealthNewsReview.org
Definitely worth a listen.
Monday, March 26, 2018
Retraction of paper on "Gut Makeover Diet" and the microbiome retracted for fundamental flaws including that it did not in any way look at the microbiome #overselling #hype #microbiomania
Made a Twitter moment that people may be interested in about a Buzzfeed article by Stephanie Lee on retraction of a deeply flawed paper supposedly connecting the Gut Makeover Diet to the microbiome and to beneficial health effects.
See below
"Gut Makeover" paper retracted for fundamental flaws #microbiome
See below
"Gut Makeover" paper retracted for fundamental flaws #microbiome
Monday, March 19, 2018
Science Magazine publishes "opinion" piece targeting a specific student w/ sexist "critique" and then won't publicly discuss what happened or what they will do about it
Well, I can't even begin to explain how disappointed I am in AAAS and Science Magazine over their actions recently. An "opinion" article was published last week in the "Working Life" section of Science which was stunningly inappropriate for Science Magazine. I first found out about this when I saw a Tweet from a colleague and friend Rebecca Calisi Rodriguez.
And when I started to dig into the story I was nauseated.I recently had a great experience publishing in @sciencemagazine's Working Life section on supporting mothers-in-science. Angry to see this now published- a personal, sexist attack on one woman (who is actually AWESOME at #Scicomm). A step back for #WomenInSTEM. Good thread here: https://t.co/KdVSqll3Rg— Rebecca Calisi Rodriguez (@BeccaCalisi) March 15, 2018
To sum up - the article was by a student who was apparently trying to express some thoughts about #SciComm activities by others that she did not like. And in the piece she named and mocked the activities of another PhD student at her own institution who does SciComm in ways she does not feel comfortable with. Fortunately, when I started looking at social media responses to this, they were overwhelmingly in support of this targeted student - Samantha Yammine who does really quite phenomenal SciComm work. (See for example her Twitter feed and her Instagram feed.
I am really thrilled and proud of the community that came out in support of her.
There have also been a few news stories related to or directly about the topic which are worth reading.
- For example T. Ryan Gregory pointed me to this one Meet the PhD student who makes science accessible through social media
- There is also this excellent piece in The Verge by Angela Chen "Scolding female scientists for embracing Instagram doesn’t solve the gender gap in STEM"
NEWS FLASH: my self-expression does not exist for you. Do not police the way I choose to interact with others and share my existence because it makes you bitter. You do you, but don't write an op-ed about why you dont want me doing me.— christine liu ✨ two photon art (@christineliuart) March 15, 2018
https://t.co/kAMulZJ6vV
YAMMMM: Yet another mostly male microbiome meeting - Microbiome Therapeutics Europe Meeting
YAMMMM: Yet Another Mostly Male Microbiome Meeting:
Microbiome Therapeutics Europe Meeting
From their speakers page I estimated gender balance of speakers
From their speakers page I estimated gender balance of speakers
19:6 M:F
or 75% male
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