New Guinea plants
From towering merbau trees to delicate orchids
When seeing the rich canopy and massive trees of the lowland canopy, one is tempted to believe that the soils are very rich. In fact, the soil layer is thin and is easily leached of its nutrients compared to the highlands.
Climbers of the forestClimbing plants, 90% of which are tropical, comprise many families. They include the climbing palms (rattans), which can reach a length of 240 m; stranglers, belonging mostly to the genera Ficus, Schefflera, Clusia, and Timonius; and epiphytes, a varied group including flowering plants and ferns.
Epiphytes include the orchids, striking plants that have successfully colonized tropical forest canopies, especially in the favourable climate of the mid-montane forests.
Some plants like it cool, cloudy and foggyBryophytes stand out from other plants described so far as being non-vascular, and neither flowering nor producing seeds. These small plants reach their greatest diversity in tropical rainforests.
They are particularly diverse and abundant in the mid-to-upper montane forests, before declining again with higher elevations. Many of them are unique to New Guinea, where they are particularly fond of areas dominated by beech (Nothofagus species).2
Trees with million-year historiesIn New Guinea, you can still find remnants of most plants of Gondwanaland, a ‘super-continent’ which more than 100 million years ago included most of the landmasses that make up Australia, New Guinea, Antarctica, South America, Africa, Madagascar, India, Arabia and New Zealand.3
How New Guinea’s plant life evolvedAfter the Australia-New Guinea continental plate broke off from Gondwanaland, it remained isolated for millions of years, preventing the invasion of foreign species. When the larger parts of New Guinea reached their current position about 10 million years ago, the island was in close proximity to others, which made possible the migration of Asian plants.
The plants we see today in New Guinea are predominantly Asian in origin, especially in the lowlands. In montane forests however, the climate favoured the evolution of new species.
Intense volcanic activity, which boomed until 200,000 years ago, resulted in the formation of rich soils at higher altitudes, which also promoted speciation.4
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