Few changes in native Australian alpine plant morphology, despite substantial local climate change

Area of Science:

• Ecology
• Evolutionary Biology
• Climate Change Science

Background:

• Rapid evolution is a key mechanism for species adaptation to environmental changes.
• Northern Hemisphere species show significant phenological and morphological shifts due to climate change.
• Limited data exists on Southern Hemisphere native species' response to climate change.

Purpose of the Study:

• To investigate the adaptive responses of native alpine plants in Australia to climate change.
• To assess changes in plant traits over the last 126 years using herbarium specimens.
• To compare adaptation rates between native and introduced species in Australia.

Main Methods:

• Analysis of over 1,500 measurements from 21 native alpine plant species in Kosciuszko National Park, Australia.
• Examination of traits including plant size, leaf thickness, leaf mass per area, leaf shape, and leaf size.
• Comparison of trait changes over 126 years with data from introduced species studied previously.

Main Results:

• Only 9% (2 out of 21) of native alpine species showed significant trait changes.
• The observed number of trait changes was not statistically significant compared to chance.
• Methodology was validated, as the same methods revealed significant changes in 70% of introduced species.

Conclusions:

• Australia's native alpine plants are not adapting to changing environmental conditions.
• Low mountain elevations limit upward migration potential for these species.
• Native alpine flora in Australia face a heightened risk from future climate change.