Deep-time discipline of ancient life: fossil record, taphonomy, mass extinctions, macroevolutionary patterns. Substrate of evolution at geological timescales.
paleobiology
Fossil record
Temporal and spatial archive of past organisms preserved in sedimentary rocks: body fossils (bones, shells, compressions), trace fossils…
Taphonomy
Study of processes (necrolysis, biostratinomy, diagenesis) between death of an organism and its recovery as a fossil. Controls preservation…
Mass extinction
Short-duration events with ≥50% species loss globally. 'Big Five': end-Ordovician (444 Ma), late-Devonian, end-Permian (252 Ma, ~90% loss),…
Cambrian explosion
Rapid appearance (~541–520 Ma) of nearly all extant animal phyla and body plans in ~20 My. Drivers hypothesised: oxygen rise,…
Punctuated equilibrium
Eldredge–Gould (1972) model: morphological stasis in species over most of their lifetime, punctuated by rapid (<100 ky, geological instant)…
Molecular clock
Divergence time estimated from sequence differences given a calibrated substitution rate (Zuckerkandl–Pauling 1965). Relaxed (uncorrelated)…
Macroevolution
Evolution above the species level — origination/extinction rates, disparity, adaptive radiations, clade-level selection. Analysed via…
Biostratigraphy / stratigraphic correlation
Use of index fossils (ammonites, conodonts, foraminifera) to correlate rock units across continents and calibrate the geological time scale…
Raup-Sepkoski kill curve + exponential survivorship: S(t)=e^(−λt); hazard=λ
Raup-Sepkoski kill-curve framework — the canonical statistical model of extinction magnitude-frequency in the marine Phanerozoic…
Jukes-Cantor 69 molecular distance: d=−3/4·log(1−4p/3); Zuckerkandl-Pauling extension
Jukes-Cantor 1969 molecular-distance framework — the canonical substitution-rate correction for multiple substitutions at the same site,…
Taphonomic preservation: P_pres=P_dep·P_surv·P_rec; Chebyshev bound 1/k²
Taphonomic preservation framework — the canonical compound-probability decomposition of the fossilisation pipeline and distribution-free…
Raup theorem: S=e^(−λt); h=λ; t_½=log(2)/λ; ⟨T⟩=1/λ; kill-curve f=C/x^k
Sympy-exact symbolic witness of the Raup-Sepkoski exponential-survivorship canonical identities and kill-curve power-law form. Setup: t,…
JC69 theorem: d=−3/4·log(1−4p/3); d≈p Taylor; t_div=d/(2μ); Var·L=−9p(p−1)/(4p−3)²
Sympy-exact symbolic witness of the Jukes-Cantor 1969 molecular-distance correction canonical identities. Setup: p, μ, L — all positive…
Taphonomic theorem: P_pres product; Chebyshev bound; 2σ=1/4; 3σ=1/9; log-sum
Sympy-exact symbolic witness of taphonomic preservation compound probability and Chebyshev distribution-free bounds. Setup: P_dep, P_surv,…
Dinosaur renaissance (Bakker 1968)
R Bakker 1968 + Ostrom 1969 dinosaur-renaissance; warm-blooded + bird-ancestry; modern feathered-dinosaurs Liaoning.
Cambrian (Conway-Morris 1989)
S Conway-Morris 1989 'Burgess Shale'; modern Chengjiang + Sirius-Passet + Marble-Canyon; molecular-developmental.
K-Pg (Alvarez 1980)
L Alvarez-W Alvarez 1980 K-Pg-iridium impact; Chicxulub crater 1991 confirmation; modern timing-debate.
Paleogenomics (Poinar 2006)
H Poinar 2006 mammoth-genome; modern Reich-lab archaic-DNA + Neanderthal + Denisovan + 240+ ancient-Eurasians.
Trace fossils (Seilacher 1967)
A Seilacher 1967 ichnofacies; modern Buatois-Mangano 2011 + ichnology Cambrian-bioturbation revolution.
Simpson 1944 tempo
G G Simpson 1944 'Tempo and Mode in Evolution'; modern modern phylogenetic-comparative + macroevolution + adaptive-radiation.
Burgess Shale (Walcott 1909)
C Walcott 1909 + Whittington 1971 + Conway-Morris 1979; modern Cambrian-explosion 530 Ma + 2024 Cambrian-Yunnan-Chengjiang fossil.
K-Pg (Alvarez 1980)
L Alvarez 1980 Ir-anomaly + 1991 Chicxulub crater; modern dust-cooling + post-impact firestorm + 2024 deep-sea-sediment Cohen.
Punctuated equilibrium (1972)
N Eldredge-S J Gould 1972 punc-eq; modern Sheets-2010 Foraminifera quantitative-test + neo-Darwinian-synthesis updates.
Trace fossils (Seilacher 1989)
A Seilacher 1989 trace-fossils + ichnology; modern modern Ediacaran-Vendian + bioturbation + paleo-environmental-reconstruction.
Paleothermometry (Shackleton 1967)
N Shackleton 1967 δ18O paleothermometry; modern Pleistocene-glacial-cycle + planktic-benthic foram coupling.