Macroevolution & long-term phenotypic evolution
Di Martino, E. & Liow, L. H. 2021 Larger offspring associated with lower temperatures across species of Microporella, a widespread colonial invertebrate Mar. Ecol. Prog. Ser. 662: 1–13. https://doi.org/10.3354/meps13656
How does offspring size change through millions of years of the history of a lineage? Using both extinct and extant species of the cheilostome bryozoan Microporella, we document offspring size changes and found that they tend to have smaller babies where it is hot, while food amount and “clutch size” do not matter for offspring size! Our study illustrates how capitalizing on among-species can reveal contrasting aspects of the variation. Read the paper for the details!
Di Martino, E. & Liow, L. H. 2021 Trait–fitness associations do not predict within–species phenotypic evolution over 2 million years Proc. R. Soc. B 20202047. https://doi.org/10.1098/rspb.2020.2047
Phenotypic selection is usually studied in contemporary populations. But won’t it be great to peer into the deep past to see changing fitness and trait evolution to give selection studies a much needed deep time perspective? But how do we obtain estimates of fitness from long dead populations? How do we know how many babies had been produced, for instance?
Cheilostome bryozoans allow us to overcome this barrier. We can estimate fecundity (a fitness component) from fossilized morphological traits (baby bags!). Using fossil populations of Antarctothoa tongima, counting the number of babies they’ve had through 2 million years we find that trait–fitness associations can be relatively stable on geological timescales although phenotypic traits show substantial change over time. Read the paper for the details!
Liow L. H. & Taylor, P. D. 2019 Cope’s Rule in a modular organism: Directional evolution without an overarching macroevolutionary trend. Evolution 73: 1863-1872
So much of the research on macroevolutionary trends are based on solitary organisms where body size has rather clear biological meaning. But what about colonial organisms? Studying module (zooid) sizes of cheilostome bryozoans through their long evolutionary history, we find that there is no dectectable trend in zooid size. However, ancestral species tend to give rise to descendent species that have larger zooid sizes than themselves. Sounds contradictory? Read our paper for explanations!
Kopperud B., Lidgard S. & Liow L. H. 2019 Text-mined fossil biodiversity dynamics using machine learning. 286:20190022 Proceedings of the Royal Society B 286 (1901) 20190022
We really wanted a dataset of observations of bryozoan taxa through geological time so we can estimate taxonomic richness and ask all kinds of cool questions about how bryozoans evolved. But we didn’t have a dataset we can play with… and we wanted a dataset yesterday, so we used Natural Language Processing tools to help us text mine bryozoan data. Who cares? Well, maybe you do if you also want a automatically compiled dataset for your favorite clade. Check out the compiled data and Bjørn Kopperud’s code here!
Ecology & Paleoecology
Di Martino E., Liow L.H., Perkins T., Portell R.W. & Taylor P.D. 2020 Sneaking up on ‘enemies’: alleviating inherent disadvantages in competitive outcomes in a nearly 3‐million‐year‐old palaeocommunity from Florida, USA. Lethaia. early online
Using a 3-million-year-old bryozoan paleocommunity encrusting jingle shells from Florida, we confirm our previous findings on overgrowth competition (Big is better!), and show how both poor and good competitors gain the upper hand by ‘attacking’ colonies of other bryozoan species from the rear and the flank…….sneaky!
Liow L.H., Reitan R., Voje K., Taylor P.D. & Di Martino E. 2019 Size, weapons and armor as predictors of competitive outcomes in fossil and contemporary marine communities. Ecological Monographs 89(2): e01354
We were curious as to whether we could predict the outcomes of competitive interactions , both in space and (deep) time. Using a community of about 80 species that we know well, we modeled the relationship between phenotypic traits and competitive outcomes. Size, weapons and armor do matter, but so do so many other factors, including stochastic ones. Our newly developed model might be useful in predicting sumo matches and Pokémon games too.
Liow L.H., Di Martino E., Krzeminska M, Ramsfjell M, Rust S., Taylor P.D. & Voje K. (2017) Relative size predicts competitive outcome through 2 million years. Ecology Letters 20: 981–988
Using communities of encrusting marine cheilostome bryozoans spanning more than 2 million years from New Zealand, we show that zooid size is a significant determinant of overgrowth outcomes (spatial competition), where colonies with larger zooids tend to overgrow those with smaller zooids. We also (serendipitously) detected temporally coordinated changes in average zooid sizes across species.
Liow L.H., Di Martino E., Voje K., Rust S. & Taylor P. D. (2016) Interspecific interactions through 2 million years: are competitive outcomes predictable?
Proceedings of the Royal Society, B 283:20160981
Using species level data on competitive overgrowth spanning more than 2 million years, we find most winner species stay winners and loser species stay losers. Bryozoans of the same species tend to cluster spatially and when they do encounter each other spatially, they stop growing at edges of encounter much more often than they try to overgrow each other. Counter-intuitively (or perhaps not) competitive ability has no bearing on ecological dominance.
Systematics & Taxonomy
Orr RJS, Di Martino E, Gordon DP, Ramsfjell MH, Mello HL, Smith AM, Liow LH 2021 A broadly resolved molecular phylogeny of New Zealand cheilostome bryozoans as a framework for hypotheses of morphological evolution. Molecular Phylogenetics and Evolution 161:107172
We present a well-supported, genome-skimmed molecular phylogeny of 200 cheilostome taxa. We find that “simple” anascan morphology can evolve into more “complex” ascophoran morphology but not vice versa in our inferred tree, the opposite of Dollo’s law! And while cheilostome systematics based on morphology is pretty great at genus and species level, “traditional” families are once again shown to fall apart. So much more work to do!
Orr RJS, Sannum MM, Boessenkool S, Di Martino E, Gordon DP, Mello H, Obst M, Ramsfjell MH, Smith AB, Liow LH (2020) A molecular phylogeny of historical and contemporary specimens of an under-studied micro-invertebrate group. Ecology and Evolution 10.1002/ece3.7042
Here we use methods to extract and sequence DNA from samples with fragmented and low concentration DNA in order to utilize older material (150 years old) to reconstruct phylogenetic history of cheilostome bryozoans, to fill gaps where fresh material is hard to access.
Liow LH, Gordon DP. 2020 New species of Adeonellopsis (Bryozoa: Adeonidae) from southern Zealandia and the western Tasman Sea. Zootaxa 4895: 301–331.
Di Martino E, Taylor PD & Gordon DP (2020) Erect bifoliate species of Microporella (Bryozoa, Cheilostomata), fossil and modern. European Journal of Taxonomy 678: 1–31
Orr RJS, Haugen MN, Berning B, Bock P, Cumming R, Florence W, Hirose M, Di Martino E, Ramsfjell MH, Sannum M, Smith AB, Vieira L, Waeschenbach A, E & Liow LH (2019) A genome-skimmed phylogeny of a wide-spread bryozoan family, Adeonidae. BMC Evolutionary Biology 19 (235)
Orr RJS, Waeschenbach A, Enevoldsen ELG., Boeve JP, Haugen MN, Voje KL, Porter J, Zágoršek K, Smith AM, Gordon DP & Liow LH (2018) Bryozoan genera Fenestrulina and Microporella no longer confamilial; multi-gene phylogeny supports separation. Zoological Journal of the Linnean Society 186(1): 190-199
Gordon D, Voje K.L. and Taylor P.D. (2017) Living and fossil Steginoporellidae (Bryozoa: Cheilostomata) from New Zealand. Zootaxa 4350: 345–362
Di Martino E., Taylor P.D., Gordon D. & Liow L.H. (2017) New bryozoan species from the Pleistocene of the Wanganui Basin, North Island, New Zealand. European Journal of Taxonomy 345: 1–15
Buskia, Microporella, Parkermavella
Di Martino, E., Taylor P. D., Gordon D., and L.H. Liow. (2016) Powellithecidae, a new Pliocene to Recent bryozoan family endemic to New Zealand. European Journal of Taxonomy 207:1–17
Powellitheca, Emballotheca, Monoporella
Rosso A., Di Martino E., Sanfilippo R., Sciuto F., and Liow L.H. (2015) Resurrection of an old forgotten name: the case of the Pliocene to Recent bryozoan Cleidochasmidra portisi (Neviani, 1895) from the Mediterranean. Bollettino della Societa Paleontologica Italiana 54: 91–102.