New paper by Sally, Catarina and Jan in Ecology & Evolution, uses COI sequences to investigate the population genetic patterns of the Antarctic brittle stars Ophionotus victoriae and O. hexactis with contrasting life histories (broadcasting vs brooding) and morphology (5 vs 6 arms). They found that, throughout the Pleistocene glacial maxima, O. victoriae likely persisted in deep sea refugia; whereas O. hexactis likely persisted in Antarctic island refugia. This work proposes the evolutionary innovations in O. hexactis (increase in arm number and a switch from broadcast spawning to brooding) could be linked to survival within island refugia, which open up new avenues for future genomic research!
New paper by Catarina and Jan in Molecular Ecology, (full article here), investigates genome-wide divergence, introgression patterns and inferred demographic history between species pairs of all six extant rock lobster species within the genus Jasus – species with a larval duration of up to two years. Funded by the Australian Research Council, this work shows the important effect of habitat and demographic processes on the recent divergence of species in the genus.
New paper by Ira, Jan and Jia in Science Advances (full article here), uses shallow whole genome sequencing to look at demographic history and selection for Acropora tenuis. The main findings are outlined in this tweet thread. Maria Nayfa also made this nice video of Ira explaining why genomes are so useful for understanding the history of the GBR.
My Octopus Teacher is a new documentary about the relationship between a man and an octopus. Jan was interviewed for her thoughts by Australian Geographic
Antimicrobial peptides are part of the innate immune system and help defend the host against pathogens and regulate the microbiome. Antimicrobial peptides occur in all life, are incredibly diverse, mostly quite small (< 200 amino acids), and only comprise of a small proportion in a genome (~ 1%). This makes them very difficult to find. We created a classification model implemented in an R package, ampir, to predict antimicrobial peptides from protein sequences on a genome-wide scale. ampir was tested on multiple test sets (including complete proteomes) and performed with high accuracy. ampir can be used to narrow down the search space for novel antimicrobial peptides in genomes.
ampir was recently published in Bioinformatics and is available on CRAN and github . Legana has also created a companion repository to accompany the paper and document the thinking behind ampir’s model building process.
In her capacity as Editor-in-Chief of Reviews in Fish Biology and Fisheries, Jan was invited by Ocean Sciences at Springer to write a blog for World Oceans Day, Monday 8 June. In the piece, Jan outlines that World Oceans Day is a moment to celebrate, and reflect upon, the critical role oceans play in our lives. She also argues that International collaboration and evidence-based policy are critical for our future oceans.
Throughout the Plio-Pleistocene glacial cycles, the Antarctic ice sheets expanded and contracted repeatedly, which led to the repeated erosion of the Antarctic continental shelf throughout glacial maxima. Even though molecular and paleontological evidence suggests most extant Antarctic benthos persisted in situ in the Southern Ocean during Plio-Pleistocene, where and how they survived remain mostly hypothesised.
Our paper recently published in Ecography synthesises current geological and ecological evidence to understand where and how benthos might have survived glacial cycles and how this challenging period might have impacted past species demography. We also examined current molecular evidence of glacial refugia in the Southern Ocean, as well as discussed future directions for employing testable frameworks and genomic methods in Southern Ocean molecular studies.
On the 10th January I sailed on the RV Investigatorfrom Perth, WA to the Southern Ocean and Southern Indian Ocean, and embarked a 57 days voyage alongside an IMAS-led research team. The main focus of the voyage was to examine Australia’s marine jurisdiction around William’s Ridge (Kerguelen Plateau), and the ancient rifting, break up and separation of tectonic plates that once connected William’s Ridge and Broken Ridge (Southern Indian Ocean). I volunteered as a molecular ecologist on this voyage to sample, identify and preserve any benthic biota that came up with deep sea rock dredges, as well as a Marine Mammal Observer (MMO) to ensure all underwater seismic operations were performed in the best interests of cetaceans (Thankfully we didn’t observe any marine mammals during our seismic days! Win-win for all mammals in the areas!).
A typical day of seismic science on the Investigator meant many happy faces in the mess during dinner time. But all would not be possible without team work between everyone on board – from the bottom deck (ship engineers who ensured ship mechanics ran right), to the operation room (where scientists and technical staff made sure the raw data were coming in as anticipated, and field operators checking all airguns were firing correctly), to all the way up the bridge (master and mates who steered the ship on the right course) and monkey island (MMOs and volunteers who made sure no cetaceans were in sight).
Whale spotting made easy when you’re staring into the “Jesus clouds”.
When seismic operation was over during each day, that’s when rock (and roll) night dredges began. In total we deployed 21 dredges and recovered benthic biota from more than half of the dredges – not a bad haul! Overall, we collected benthic fauna from depths between <1000 m and >4000 m, including animals from various taxa such as annelids, brachiopods, bryozoan, cnidarian, crustaceans, echinoderms and poriferans. We have now transported these specimens safely back to WA museum and hopefully they will be interesting assets to the collections!
Patiently waiting for the rock dredge to come up on deck. Photo credit: Adrian Koolhof.
Life on a ship can be a bit tough during rough weather (e.g. 10 m swell on valentine’s day) but the amount of interesting science and activities that were happening had made it very worthwhile to be on a research cruise in the Southern Ocean. Before this trip, I had never thought I could understand birds, geology and ship mechanics but here I am – a proud twitcher with a brain full of knowledge of rocks, seismic, mapping and ship science! I am very thankful to the science party (esp my awesome lab partner Paige Maroni), medical staff on board and the crew who made this such a rewarding experience.
First animal collected on this voyage – a crowd favourite after speaking about brittle star genomics during transit! A rare calm day in the Southern Ocean.
New paper in Journal of Proteome Research by group alumnus, Nikeisha Caruana uses quantitative proteomics to understand slime secretions in striped pyjama squid. For this work Nikeisha used a multi-tissue comparison to hone in proteins unique to slime-producing glands. The work is also the first time these glands have been described in detail and their proteomic similarity to the slime and physical structure implicates them as likely secretion structures.
