biodiversity-utac

GenesisAeon Package 115 — real, independently verified habitat- fragmentation thresholds and coextinction-cascade science. Second of the three remaining candidate gap-topics from UTACnextSteps.txt (after coral-reef-utac, P114). Deliberately has no UTAC/CREP/AFET bridge and no invented Γ value — see DISCLAIMER.md.

Deliberately not one-sided

does_a_worsening_aggregate_trend_mean_intervention_is_futile() returns False — Simkins et al. (2025) reviewed 67,217 species and found that specific, documented conservation actions measurably improved individual species' status even while the aggregate biodiversity trend continued downward. Collapse-mechanism science and "intervention works" are both real; this package documents both.

What's real here

• Andrén (1994, Oikos) — a real, foundational review: where 30% or more of original habitat remains, fragmentation itself doesn't add measurably to species-richness decline beyond habitat loss alone. Below 30%, fragmentation effects compound habitat loss.
• Koh et al. (2004, Science) — a real, published probabilistic coextinction model: ~6,300 affiliate species are "coendangered" with already-endangered hosts, and roughly two-thirds of 9,650 modeled interspecific systems could collapse if one partner is lost.
• IUCN Red List (current) — 169,420 species assessed, 47,187 (~28%) threatened; the first Global Tree Assessment found 38% of assessed tree species at risk — disproportionately high, and directly relevant to coextinction risk since trees are foundational habitat.
• WWF Living Planet Report 2024 — real, tracked population-trend index across almost 35,000 vertebrate populations (5,495 species, 1970–2020): terrestrial populations down 69% on average (freshwater, the steepest biome, is already covered by freshwater-ecosystem-stressors-utac, P106, so this package uses the terrestrial figure to avoid duplicating that number).
• Simkins et al. (2025, PLOS Biology) — the honesty-check citation: a real, large-sample review showing targeted conservation actions produce real positive outcomes even amid a real, worsening aggregate trend.

Quickstart

pip install biodiversity-utac

from biodiversity_utac import (
    does_fragmentation_compound_habitat_loss, ANDREN_THRESHOLD,
    systems_at_collapse_risk_count, COEXTINCTION_ESTIMATE,
    fraction_of_assessed_species_threatened, REDLIST_STATUS,
    LPI_TERRESTRIAL,
    does_a_worsening_aggregate_trend_mean_intervention_is_futile,
)

print(ANDREN_THRESHOLD.habitat_remaining_threshold_pct)  # 30.0
print(does_fragmentation_compound_habitat_loss(20.0))    # True
print(systems_at_collapse_risk_count())                  # ~6433
print(round(fraction_of_assessed_species_threatened(), 3))  # ~0.279
print(LPI_TERRESTRIAL.terrestrial_decline_pct)            # 69.0
print(does_a_worsening_aggregate_trend_mean_intervention_is_futile())  # False

Development

pip install -e ".[dev]"
pre-commit install
ruff check src tests
mypy src
pytest

Citation

See CITATION.cff and .zenodo.json.