Three of the supplied papers directly address the query. In the Northern Great Lakes region, 14,076 museum and field records show southern species expanding and northern species contracting since 1981: white-footed mice (Peromyscus leucopus) rose from 38.3% to 77.7% of captures while woodland deer mice (P. maniculatus gracilis) fell from 28.0% to 5.9%, and opossums (Didelphis virginiana) appeared from zero to 35.5% β an observed, warming-consistent community reassembly attributed to climate change, though historical collection records carry collector-bias risks .
Forward-projected SDMs predict the yellow-bellied glider (Petaurus australis) loses 62β78% of distribution under low warming by 2050β2070 and 100% under high warming, based on 57 Wet Tropics and 428 SE Queensland occurrence records with MaxEnt (AUC 0.991 on BIO8, mean temperature threshold ~22 Β°C vs 26.5 Β°C at random sites) .
A complementary paleo-perspective uses sedimentary ancient DNA (116 samples, 4 marine cores) to reconstruct 12,000 years of marine mammal distribution shifts in Northern Greenland, showing species responded to Holocene deglaciation earlier than fossil records suggest .
Step 1 β Data acquisition: harvest occurrence records (GBIF, MaNIS, museum databases) with coordinate cleaning in Python (pandas + geopy), matching the glider study's 485-record and Great Lakes study's 14,076-record scales; download WorldClim bioclimatic layers, prioritizing BIO8-type temperature variables identified as strong predictors.
Step 2 β SDM pipeline: replicate and extend the MaxEnt framework in Python (scikit-learn Maxent replacement or R via rleaflet/sdm): fit current and future projections (2050/2070, low/high emissions), report AUC on spatially blocked cross-validation (the reported AUC 0.991 may reflect overfitting to a small Wet Tropics sample of 57 records β a key limitation), and quantify core-habitat loss as % distribution lost per scenario.
Step 3 β Community shift analysis: bin record sets by pre/post warming thresholds (as the 1981 split), compute relative-abundance change per species, and test latitude/temperature associations with GAMs (statsmodels/pyGAM), mirroring the Great Lakes approach while correcting for collector bias via effort-modeling.
Step 4 β Validation against deep time: use sedimentary aDNA presence/absence time series as an independent empirical benchmark for SDM skill on past climate analogs.
Limitations/blindspots: SDMs omit biotic interactions, dispersal, and habitat quality (acknowledged in the glider study); historical record biases (misidentification, uneven sampling) affect the observed shifts; both projected and observed patterns are correlational with warming, so attribution requires experimental or multi-region replication.
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