Even rainforests without dry seasons run on a yearly clock
Dias PAD, Rangel Negrín A
Phenology
If you've ever assumed tropical forests just do their own thing year-round with no rhyme or reason, this shows that flowering, fruiting, and leafing out follow a reliable annual rhythm even where it rains almost constantly, the same kind of pattern that tells you when your garden's fruit trees will bloom.
Scientists tracked 480 trees every week for 10 years in a super-wet Mexican rainforest that gets rain almost year-round, expecting the timing of leaves, flowers, and fruit to be pretty random since there's no real dry season to trigger anything. Instead, they found a surprisingly consistent yearly schedule: flowers peaked reliably each April, and young leaves and flowers tended to show up together for weeks at a time, year after year. It turns out that even without a dry season pushing things along, these forests still run on a dependable internal calendar.
Key Findings
Flowers showed the strongest seasonal peak (concentration r = 0.52, Fourier R2 = 0.93), reliably clustering around April, while mature leaves showed the weakest seasonality (r = 0.08)
Seasonal (within-year) variance dominated phenological patterns for all five phenophases studied; year-to-year variance was negligible except for mature leaves (18.0%)
Annual timing was highly repeatable across the 10 years (ICC = 0.58-0.88), and young leaves and flowers consistently co-occurred for about 15 weeks each year (correlation r = 0.72 on average)
chevron_right Technical Summary
A 10-year study of 480 trees in a Mexican rainforest found that even in a climate with rain nearly all year, trees still follow a predictable annual calendar for growing leaves, flowering, and fruiting. This means tropical forests aren't as unpredictable as scientists once assumed, which matters for planning conservation and understanding food supply for forest animals.
Abstract Preview
Original paper
Seasonal structure, multi-scale variance, and inter-annual consistency of plant phenology in a Neotropical perhumid forest.
Plant phenology is a key determinant of the productivity and trophic dynamics of tropical forests, yet the multi-scale variance structure and inter-annual consistency of community-level phenologica...
open_in_new Read full abstractAbstract copyright held by the original publisher.
Was this useful?
Want to tell us more? (optional)
Thanks for the note!
Something went wrong — please try again.
Too many submissions. Try again in an hour.
Street trees cut heat deaths by 39 percent in European cities
Trees in your local park or street aren't just pretty — they are literally keeping people alive during heatwaves, and planting even a modest number of the ri...
Climate adaptation in plants refers to the physiological and evolutionary mechanisms through which plants adjust to changing environmental conditions, including temperature shifts, altered precipitation patterns, and seasonal variations. Understanding these processes is essential for plant science
arrow_forward Explore topic