6/🧵 No evidence of inbreeding in the ‘ō’ū 🦜 – likely large populations prior to its decline. Loss of a highly frugivorous #Hawaiian #honeycreeper = ⬇️ functional diversity in a clade where ~72% species diversity has disappeared. 15/17 remaining species are endangered and thus of conservation concern

5/🧵 #Admixture has seldom been detected in #Hawaiian #honeycreepers. We find:
❌ no evidence that ‘ō‘ū 🦜interbred with kiwikiu 🐦
✅ significant evidence of gene flow from Lāna’i ‘ō‘ū 🦜into the Lānai hookbill🐤 (extinct in early 1900s)
highlighting a pre-extinction breeding strategy in this clade

4/🧵 Most Hawaiian honeycreeper lineages diversified: different species on different islands. Our ‘ō‘ū population structure results suggest speciation initiation – a distinct Kaua’i population (PC1) and minimal differentiation between other islands. But why are the Lāna’i birds so different?! (PC2)

3/🧵 ‘Ō‘ū display sexual dimorphism in head colour – females: olive green, males: yellow. Our morphometrics on 89 ‘ō‘ū specimens also show dimorphism – in size, with smaller females. Further, males are differentiated between islands – the largest on Kaua’i (most isolated) smallest on Maui-Nui islands

2/🧵 Dataset: our morphometric 📐 & genomic 🧬 data come from 12 different museum collections! Almost all samples from the 1800s. We genomically analysed 49 ‘ō‘ū + the only known Lāna’i hookbill 🐤 specimen using ancient DNA methodologies + target capture. The only extant specimen used: a Maui kiwikiu🐦

1/🧵 Today at #BOUasm25, I’m presenting on the ‘ō‘ū 🦜 a parrot billed-like #Hawaiian #honeycreeper, last seen in 1989. We dive into its population ecology and investigate – did it interbreed with other parrot-billed Hawaiian honeycreepers prior its extinction? doi:10.1098/rsbl.2025.0265 #ornithology

grateful for the opportunity to present in this fantastic session on plants animals and epidemics at ISBA last month @isbarchaeology.bsky.social