Updated: May 4
The full article below is written by our partner at 1StopBorneo.
Birdwing butterflies are known for their flight pattern, resembling that of a bird. Their unique angular wings and relatively large body size (up to 28cm long in width) also made them highly distinguishable from the other butterfly groups.  One such species, the Rajah Brooke's Birdwing butterfly (Trogonoptera brookiana), is found throughout Peninsular Malaysia with groups of 300 individuals sometimes observed congregating around stable geothermal springs.  If you don't already know, the Rajah Brooke's Birdwing butterfly is also Malaysia's national butterfly! Don't try to catch one to sell though, almost all species of birdwing butterflies (including our national butterfly) are listed under CITES's Appendix II, thus protecting them from illegal trade. 
Photo Credits: DirkHeumannK1966, Wikimedia Commons (CC BY-SA 4.0)
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 Phon, C., Kirton, L., & Yusoff, N. (2017). Monitoring butterflies using counts of puddling males: A case study of the Rajah Brooke's Birdwing (Trogonoptera brookiana albescens). PLOS ONE, 12(12), e0189450. doi: 10.1371/journal.pone.0189450
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