Tanja Pyhäjärvi

@pyhatanja.bsky.social

Professor in Forest Genomics and Breeding, Faculty of Agriculture and Forestry, University of Helsinki, Finland Loves gymnosperms and bad behavior, best when combined!

Our brilliant PhD students are at #SMBE2026 ! S22: P334 Rachel Carboni with snMultiomics S22: P339 @xindih.bsky.social with epistasis vs modularity in GRNs (w/ @fishcongen.bsky.social) S22: talk at 17:45 @jennisiren.bsky.social with GxE in gene expression (w/ main sup @pyhatanja.bsky.social)

Society for Molecular Biology and Evolution@official-smbe.bsky.social · 2mo ago

#SMBE2026 S22: Evolution of gene regulation: insights from novel molecular and statistical approaches 🗓️ Wed Jul 1, 1:20pm - Part 1 🗓️ Wed Jul 1, 3:50pm - Part 2 🔗 smbe2026.org/programme

We are looking for a PhD researcher to work for the “ClimatePine” -project, conducted in collaboration among Natural Resources Institute Finland, Metsähallitus Forestry Ltd and University of Helsinki. More info: valtiolle.fi/en/jobs/rese...

Research Scientist, doctoral researcher, forest breeding - Natural Resources Institute Finland

Open job: Research Scientist, doctoral researcher, forest breeding, Natural Resources Institute Finland - Find all jobs in Valtiolle.fi

valtiolle.fi

We're looking for a new colleague at Asssoc Prof level! Come join us in the Zoology Department at Stockholm University. A teaching profile in ecology, faunistics and/or physiology is beneficial. Find the full job advertisemnt here: su.varbi.com/en/what:job/...

Associate Professor in Zoology with focus on ecology and evolution

Department of Zoology  at Stockholm University includes ca. 80 employees counting researchers, PhD students, and administrative staff. Research and education at the department occurs in an internatio

su.varbi.com

What a memorable day to give and listen to inaugural lectures of new professors at University of Helsinki! Here we are after the lectures with colleagues Fred Stoddard and Anne-Maria Pajari and the dean Ritva Toivonen from the Faculty of Agriculture and Forestry. @helsinki.fi

Bild

It is a little bit depressing that 80 % of papers applying population genetic methods typically estimate π (nucleotide diversity per bp) wrong, and even worse, do not realize that when looking at the point estimates.

Baffling failure of a well-studied trade-off in plants to survive the transfer from greenhouse studies to the open field. Intriguing study from @derekseveri.bsky.social @plantevolution.bsky.social and colleagues in @plosbiology.org

PLOS Biology@plosbiology.org · last yr.

In the greenhouse, #Arabidopsis with hyperactive ACD6 have stronger pathogen defenses but are smaller & make fewer seeds. @derekseveri.bsky.social @plantevolution.bsky.social &co show that in the open field both advantages & disadvantages of the allele disappear @plosbiology.org 🧪 plos.io/465XPDR

A hyperactive ACD6 allele reduces growth and causes necrosis only in the greenhouse. Top:  Representative Arabidopsis thaliana rosettes from different genetic backgrounds. Yellow and blue labels represent descendants of a heterozygous ACD6 HIF line that are homozygous for either the Est-1 or the Col-0 allele of ACD6. Green and purple labels represent the Est-1 accession and the isogenic acd6 knockout null allele in that accession. Plants were grown in Tübingen in the greenhouse (GH-Tü), outdoors in the field in Tübingen (F-Tü), or outdoors in the field in Zurich (F-Z, a GMO-approved facility). Note the necrotic older leaves for greenhouse plants with the ACD6-Est-1 allele (red arrows). Bottom: Rosette size of individual plants, calculated by quantifying green pixels from images similar to those in the top panel. The line within each box represents the median. Boxes enclose the interquartile range (IQR) with whiskers extending to up to 1.5 times the IQR. Brackets indicate Mann–Whitney U-test results, with * indicating P < 0.05 after Benjamini–Hochberg correction for multiple testing across the four comparisons. Dotted lines extending from the mean of each distribution span the observed effect size, and a bootstrapped distribution of computed effect sizes [30] is shown in gray, centered on the mean of the second box in each pair (red dot). The black bar extending vertically from the red dot represents the 95% confidence interval of the effect size.

You know over the years what I have been really bothered by? When I was in college, bryophytes were taught as if they were relics of the past. Its sole purpose was to demonstrate trait progression leading to angiosperm, w/o mentioning their importance in nature, research, or potential in biotech.

Who started this ridiculous habit of using K for thousands? 10K run? 10 kelvin run is freezing! And now in scientific writing too. I know there are big battles going on now, but I will focus on this one instead.

Still waiting for a reimbursement from a US University that invited me there to give a talk last August. My advice: do not ever pay the travel expenses yourself when invited and promised reimbursement.

I'm excited to share our new preprint on the molecular evolution of heterodichogamy in two wingnut genera of Juglandaceae. Heterodichogamy features two morphs synchronously alternating male and female flowering phases in time to generate disassortative mating. doi.org/10.1101/2025...

Pictures of two dichogamy morphs in Pterocarya trees, a graph visualizing flower dimorphism, and a phylogeny of the Juglandaceae family showing divergence times and origins of genetic systems for heterodichogamy.