Leaf margin types of angiosperm woody species show distinct distribution pattern across latitude: toothed species are dominant in middle to high latitude, whereas species with entire margin are dominant in low latitude. This pattern has been confirmed in multiple continents and is important for inferring paleoclimate. However, its underlying mechanism is still unknown for over 100 years, partially because limited number of species and locations has been examined.

Here, we compiled a dataset of 16 leaf traits reflecting plant ecological strategies in resource acquisition and process (e.g., photosynthetic rate, leaf hydraulics) for 2325 woody species across the globe from published literature. Our aim is to explore the functional significances of leaf margin types, considering the effect by leaf functional types, growth form and biomes.

Toothed species were characterized by shorter leaf lifespan, lower leaf construction cost, and lower primary and secondary vein density than entire leaves independent from leaf functional types. Mass-based photosynthetic rates were higher for toothed leaves than for entire leaves in evergreen species.

These results suggest toothed species would be favored in the region with shorter growth period via lower leaf construction cost but the similar or higher (in evergreen species) photosynthetic rate than entire-margined leaves.