Life table response experiment
For species with significant differences in population growth rates with
and without neighbours (A. calendula and P. debilis ), we
used life table response experiment (LTRE) analysis to decompose
differences in population growth rates into contributions from each
transition between life stages. We modelled a simple two-stage life
cycle of seeds and adults with a one-year time step estimated in Spring,
before seed rain (Figure S2). We also included seed dormancy
probabilities to incorporate the potentially important role of the seed
bank (Nguyen et al. 2019, see Supplementary Methods). Using the
“exactLTRE” package (Hernández et al. 2023), we carried out
directional fixed design LTRE using intrinsic lambda (in the absence of
neighbours) as the reference matrix compared to lambda in the presence
of neighbours as the treatment.