Anne Stone

Distribution of reproductive success for adult male sloths (i.e., number of offspring sired per male; n = 20 total males). Non-grey bars correspond to males that produced offspring. Inset: Home ranges of adult male and female sloths across habitat types, where black lines correspond to home ranges of females that reproduced, white lines correspond to females that did not reproduce, and grey lines correspond to males that did not reproduce.

The brown-throated sloth lost this round and in fact, many males in this species lose when competing for mates! Using 13 microsats, a small study found that 50% of all juveniles were sired by 1 male (and 74% of males did not reproduce at all!). #2026MMM #RIP doi.org/10.1371/journal.pone.0051389

Left: mtDNA-based phylogenetic relationships of all extant xenarthran species (sloths, armadillos, and anteaters), including the brown-throated sloth (Bradypus variegatus). Right: Divergence times for all extant xenarthran species based on mtDNA. Vertical lines define the main geological periods of the Cenozoic (E = early; M = middle; L = late; Pli. = Pliocene; P. = Pleistocene)

Did you know the 6 species of sloths still around today are classified as either two- or three-toed sloths? The brown-throated sloth is a three-toed sloth and mtDNA suggest that it, along with the other three-toed species, diverged from two-toed sloths ~30 mya! #2026MMM doi.org/10.1093/molbev/msv250

This phylogenetic tree marks with red arrows the pseudogenization (gene becoming nonfunctional) of PADI3 and S100A3, two hair-related genes. The two groups seem to have lost these genes independently. This is an example of convergent evolution in two aquatic animals.

Hippos are the closest relatives to cetaceans (whales, dolphins), but these two groups lost their hair independently. Genetics show that hair-related PADI3 and S100A3 became nonfunctional pseudogenes AFTER these two groups split. #2026MMM doi.org/10.1007/s002...

Analysis of population structure of microsatellite data using five distinct software (A-E) showing varying levels of structure in beech martens across the Iberian Peninsula.

Using mitochondrial and microsatellite data, Vergara et al. (2015) found that there is weak genetic structure of beech martens across the Iberian Peninsula, possibly driven by the rivers Ebro, Tagus, and Guadiana, which create semi-permeable geographic barriers. doi.org/10.1371/jour... #2026MMM #RIP

Model of the demographic history for members of the family Elephantidae. TFS = forest-savanna elephant divergence time, TAM = Asian elephant-mammoth divergence time, TLox-Eur = African-Eurasian divergence time, and TElephantid-Mastodon = to elephantid-mastodon divergence time (all in in millions of years). Ν values = diploid effective population size preceding each split (in thousands).

Asian, African savanna, and African forest elephants are the only 3 species of elephantids left today.>300 sites in the genome suggest that the Asian elephant is most closely related to their famous extinct elephantid relative, the iconic woolly mammoth. #2026MMM doi.org/10.1371/journal.pbio.1000564

Violin plot showing the heterozygosity across a number of different carnivores (including the beech marten (Martes foina) as well as their conservation status.

Tomarovsky et al. used cytogenetics and DNA sequencing to reveal that the stone marten has a karyotype (# and arrangement of chromosomes) similar to the ancestral carnivoran karyotype. Low heterozygosity suggests that its conservation status should be re-evaluated. doi.org/10.1093/jher... #2026MMM

Researchers used the BOTTLESIM program to predict genetic diversity in giant anteaters over next 100 years if 100% (blue), 75% (red), 50% (gray), 25% (yellow), and 10% (green) of the current effective population size is maintained. (A) Number of alleles. (B) Number of effective alleles. (C) Expected heterozygosity. (D) Observed heterozygosity.

Giant anteater's loss mirrors its real-world decline. Genetic simulations predict a 15% drop in allelic richness over the next 100 years even if current numbers are held. Stopping threats like roadkill and hunting is urgent to ensure this species's viability. #2026MMM #RIP doi.org/10.3389/fgen...

The median joining network maps are color-coded according to their biomes of origin. Given that a lot of the circles (representing unique haplotypes) are found in diverse biomes, it indicates that giant anteater lineages are found across diverse locations.

Giant anteater genetics confirm that they are habitat generalists. Haplotypes for both mitochondrial and nuclear markers are shared across biomes like Cerrado, Pantanal, and Amazonia. This suggests high connectivity and movement across diverse landscapes. #2026MMM doi.org/10.1007/s105...

FGFRL1 gene has 7 amino acid substitutions that are unique in giraffes but fixed in other mammals (see “Unique”) and/or predicted to alter the protein’s function (see “Polyphen”).

Comparing mutations in the genomes of the giraffe vs. other mammals helps scientists find genes possibly responsible for the giraffe’s uniquely long neck. 7 changes in FGFRL1 (gene involved in skeletal + cardiovascular development) might provide important clues. #2026MMM doi.org/10.1038/ncomms11519

Fluorescence over time of reactions amplifying Cytochrome B DNA. This genetics test uses primers (short DNA fragments) that only bind to chital DNA. A fluorescence signal is reported only in meat samples from chital deer. This test is fast (under 30 minutes), and requires minimal equipment that can be used in the field.

Wildlife officials combat illegal hunting of chital deer, but their meat is not easy to recognize. Scientists created a fast DNA test that only fluoresces when chital DNA is present, which helps identify meat in the field to prevent illegal trading. #2026MMM #RIP doi.org/10.1007/s126...

PCR products amplifying the amelogenin and SRY genes of deer environmental (tissue and fecal) samples were run on an agarose gel. Male samples show 3 bands (odd number lanes) while female samples show 1 band (even number lanes). A similar test can also be used to distinguish between different deer species.

Field biologists may identify a species from environmental samples, but determining its sex may require genetic tests. A PCR reaction can identify the sex of chital tissue or fecal samples. A 5:1 male to female ratio was found from samples in India doi.org/10.1007/s120... #2026MMM

A parsimony network shows the distribution of rhino mitochondrial DNA haplotypes from individuals in each of the 2 remaining wild populations: Nepal and Assam.

There are two remaining Indian rhinoceros populations. Genetic sequencing of rhinos from these two sites showed that Assam is the historical source while the Nepal group formed later when individuals moved from Assam #2026MMM doi.org/10.1016/j.bi...

"Squirrel sampling sites in the British Isles. Pie charts indicate the location of sites where squirrels were sighted or found and are color-coded as indicated in the box; numbers within circles indicate different animals tested where N > 1. Boxed circles refer to squirrels of unknown location. I, Ireland; S, Scotland; A, Isle of Arran; B, Brownsea Island; W, Isle of Wight. The figure was drawn in R (v3.2.23) with the package maps (v3.1.0) using the mapdata (v2.2-6) “worldHiresMapEnv” and the package plotrix (v3.6-2) for pie charts. "

Avanzi et al. (2016) analyzed DNA from wild roadkill red squirrels & discovered some carry Mycobacterium leprae & M. lepromatosis which cause Hansen’s disease (aka leprosy). Also the strains of M. leprae were similar to those found in Medieval England! #2026MMM #RIP www.science.org/doi/10.1126/...

Neighbour-joining tree (Tamura–Nei) of cytochrome b haplotypes of various Sciurus species for which data was available from GenBank. Bootstrap values obtained with 2000 replicates. Distributions of the species are indicated with shades or circles: Sciurus vulgaris (Eurasia), S. v. meridionalis (southern Italy), S. lis (Japan), of S. aberti, S. niger, S. carolinensis, and S. stramineus (North America). From Grill et al. (2009) doi: 10.1111/j.1365-294X.2009.04215.x

Grill et al. (2009) used mt DNA & microsatellites to study red squirrel population history finding that Calabrian squirrels are distinct & may be from a ‘refuge w/in refugia’ remaining isolated in the Pleistocene after which the rest of the squirrel crowd expanded doi.org/10.1111/j.13... #2026MMM

The proportion of each whale’s genome that is inbred (as measured by runs of homozygosity [ROH] larger than 1 million base pairs). Each vertical bar corresponds to an individual genome. Genomes of historic Southern Ocean whales from the early 1900s [HIS] are colored brown, contemporary Southern Ocean whales [SOU] are colored blue, and contemporary North Atlantic whales [NAT] are colored green.

Mid-1800s ➡️ early 1900s, humpback whales dramatically ⬇️ due to hunting. The species has showed signs of recovery but their DNA still may harbor the cost of this decline; they have slightly ⬇️ genetic diversity and are slightly ⬆️ inbred than early 1900 whales. #2026MMM doi.org/10.1126/sciadv.ady7091

Animals on MONEY

WELCOME WELCOME WELCOME
to the first night of ROUND 1
MONEY MAMMALS DIVISION!
#2026MMM

Camel train against a sunset sky.

DID YOU KNOW ABOUT THE CAMEL MOBILE LIBRARY?!

Each issue of the #2026MMM MMMagazine gives the science behind the battle, but also has so much more! Last night's LIBRARY column led by Janice Hermer, explained how no matter your interest, there's a library for that!
libguides.asu.edu/MarchMammalM...

the word dna is displayed on a screen with a glowing background . Alt: the word dna is displayed on a screen with a glowing background .

Thanks to @lucasrocm.bsky.social for tonight's genetics skeets! Join us on March 11 for more amazing genetics #2026MMM facts!

Bayesian consensus of Hyposmocoma showing 95% confidence intervals of posteriors . Numbers above branches are Bayesian posterior probabilities (PP) and ML bootstrap values (BP), respectively. Coloured circles indicate microhabitat types and ancestral state probabilities.

Hawaiian Hyposmocoma caterpillars show near-identical “purse case” larval homes, despite evolving independently twice in rotting wood (NW islands ~15–9 Ma, main islands ~3 Ma). DNA phylogeny of 38 spp. reveals convergent design under similar pressures. doi.org/10.3897/zook... #2026MMM
#RIP #2026MMM

a man is holding a small white dog and says it rubs the lotion on its skin or else it gets the hose again . ALT: a man is holding a small white dog and says it rubs the lotion on its skin or else it gets the hose again .

ooof this made me think of Silence of the lambs 😱

Best Reduviinae tree based on RAxML analysis of 178 taxa using a partitioned molecular dataset of 5 gene regions (16S, 18S, 28S D2, 28S D3–D5, Wg). Bootstrap values are indicated on branches by colored triangles according to support strength. Reduviinae lineages are indicated as red branches and remaining reduviids as blue while outgroup taxa are black. The shaded red box highlights members of the hematophagous Triatominae, here shown as paraphyletic. Red arrowheads refer to the polyphyletic Cetherinae; the asterisk refers to Physoderinae nested within a reduviine clade.

The subfamily Reduviinae (Assassin bugs) is a taxonomist's nightmare. A molecular phylogeny done by Hwang & Weirauch (2018) reveled it is polyphyletic, meaning the group doesn’t share a single recent ancestor. doi.org/10.1371/jour... #2026MMM

Molecular phylogeny of Hyposmocoma lineages based on 38 genes and 82,875 aligned base pairs. 95% highest posterior density confidence intervals for the molecular dating estimates for nodes are indicated with blue bars. Different lineages are indicated by their larval case type, and exemplar cases are shown on the right. Bone collector and cigar case species are the only ones that are carnivorous. Current terrestrial areas of the Hawaiian Island chain are shown in dark green; shallows that were once above sea level are shown in gray. The islands are placed along the timescale according to age and geographic position.

Bone collector caterpillar (Hyposmocoma) comes from one of Earsth's most diverse adaptive radiations with 350+ Hawaiian spp. Phylogenomics finds 9 major lineages. Yet this one is monotypic (no sister species), split from its carnivorous relatives >5M years ago. DOI: 10.1126/science.ads4243 #2026MMM

Stylized "wild card" cards of both insects wearing their corpse suits (described in coming battle).

FIRST & ONLY UP TONIGHT: Bone Collector Caterpillar (Hyposmocoma) vs. Assassin Bug (Acanthaspis petax) #2026MMM

a man with a beard is standing next to a woman with the words `` there can be only one '' . Alt: a man with a beard is expressing `` there can be only one '' .

& importantly, remember, MMM features 65 species, but only one will be crowned THE FOURTEENTH CHAMPION #2026MMM

a close up of a man 's face with the words that there 's some good in this world mr. frodo ALT: a close up of a man 's face with the words that there 's some good in this world mr. frodo

Time has NOT run out, & each of us can make an impact on recovering our ecosystems & reducing our use- through our time, through our effort, through our political engagement, through our thoughtful conversations with loved ones. #2026MMM

a herd of elephants standing in a field with birds flying around them Alt: a herd of elephants standing in a field with birds flying around them

In coming weeks we will share in a journey across our world, & occasionally through time, in a celebration of animals, adaptations, ecosystems, and our coMMMunity #2026MMM

a satellite image of a hurricane taken on august 18 ALT: a satellite image of a hurricane taken on august 18

And March Mammal Madness would not be possible without the incredible achievements of scientists the world over, so many funded by those historical engines of excellence- the National Science Foundation, the National Institutes of Health, the National Oceanic and Atmospheric Admin #2026MMM

a close up of a dna molecule on a dark background ALT: a close up of a dna molecule on a dark background

And @acstone.bsky.social & @cegamorim.bsky.social for bringing together an incredible team of geneticists to unlock the mysteries of the genome of the combatants in each battle! The science, it's so beautiful! #2026MMM

a bunch of zebras in a field with the words " it 's in our blood " above them Alt: a bunch of zebras in a field with the words " it 's in our blood " above them

#2026MMM cont. Genetics Team: @afogel29.bsky.social
@carloschalicothere.bsky.social
@elinork.bsky.social
@elliecat.bsky.social
@fervillanea.bsky.social
@lucasrocm.bsky.social
@sexchrlab.bsky.social
@n8upham.bsky.social

LibGuides: March Mammal Madness: Tournament Results The official home for March Mammal Madness tournament information and resources! If you're learning, you're winning!

All March Mammal Madness results will be available at the LibGuide in MMMAGAZINE, text (in English & Spanish), play-by-play, and VIDEO FORM in the minutes and hours after the events happen here libguides.asu.edu/MarchMammalM... #2026MMM