range offset of taxon

Determines temporal and stratigraphic range offset, a measure of biostratigraphic precision, as a function of time of extinction, fossil abundance, stratigraphy, ecology, and taphonomy. Effectively a high-level wrapper around last_occ, p3/p3_var_rate, apply_niche, apply_taphonomy and time_to_strat/strat_to_time from the admtools package.

Usage

range_offset(
  t_ext,
  rate,
  adm,
  niche = trivial_niche,
  gc = trivial_gradient,
  niche_domain = "time",
  pres_potential = all_preserved,
  ctc = perfect_preservation,
  taphonomy_domain = "strat"
)

Arguments

t_ext

true time of extinction

rate

either positive number or a function. If a number, rate of fossil occurrences passed to p3, if a function passed as rate function to p3_var_rate

adm

age-depth model

niche

niche model, by default the trivial niche

gc

gradient change for the niche mode, by default the trivial gradient. See ?apply_niche

niche_domain

"time" or "strat" - in which domain should the niche model be applied?

pres_potential

preservation potential of fossils, by default all preserved (no taphonomic effects)

ctc

change in taphonomic conditions, by default no change in conditions. See ?apply_taphonomy

taphonomy_domain

"time" or "strat" - in which domain should the taphonomic effects be applied?

Value

a named vector with two entries:

• "h": distance between last occurrence and true height of extinction

• "t": time between last occurrence and true time of extinction

See also

last_occ() determine position/time of last occurrence of taxon

Examples

# last occurrences 2 km from shore
h = scenarioA$h_m[,"2km"]
adm = admtools::tp_to_adm(t = scenarioA$t_myr, h = h)
offset = range_offset(t_ext = 1.8, rate = 5, adm = adm)
offset # show timing and position of last occurrences
#>          t          h 
#>  0.6411079 14.2482949