This study set out to demonstrate that bioluminescence in Motyxia evolved in a common ancestor and grew brighter through evolutionary time.
How did they do this?
Existing research had already demonstrated that 10 discovered species of Motyxia had different levels of bioluminescence. By measuring the variance in the brightness between species, the authors of the study attempted to gain an insight into how their bioluminescence evolved.
An experiment was set up to measure the brightness of each species. The experiments used a number of wild species of Motyxia and a control group of closely related millipedes which do not have bioluminescent properties, all from the genus Xystocheir (Figure 1).
While observing the millipedes in the absence of light, one of the …show more content…
(Figure 1)
Tests for relationships/directional trends
Figure.2 shows the tests of relationship between bioluminescence and toxicity (cyanide gland area) with phylogenetic distance from the root. A and C are the relationships for luminescent millipedes, while B and D are graphs for non-luminescent millipedes.
What did they find?
Results of DNA analysis
The results showed that X.bistipita actually belonged in the Motyxia genus and was renamed accordingly.
The results also seemed to show that bioluminescence only evolved once in all millipede species and is an exclusive characteristic of the genus Motyxia.
Analysing the relationships
In millipedes of the genus Motyxia, there exists a positive linear relationship between the brightness of the millipede’s glow and the distance from the root of the phylogram (A).
A comparable relationship also exists between toxicity and phylogenetic distance (C).
No strong correlations were observed for the non-bioluminescent taxa (B) and (D).
What can we
How did they do this?
Existing research had already demonstrated that 10 discovered species of Motyxia had different levels of bioluminescence. By measuring the variance in the brightness between species, the authors of the study attempted to gain an insight into how their bioluminescence evolved.
An experiment was set up to measure the brightness of each species. The experiments used a number of wild species of Motyxia and a control group of closely related millipedes which do not have bioluminescent properties, all from the genus Xystocheir (Figure 1).
While observing the millipedes in the absence of light, one of the …show more content…
(Figure 1)
Tests for relationships/directional trends
Figure.2 shows the tests of relationship between bioluminescence and toxicity (cyanide gland area) with phylogenetic distance from the root. A and C are the relationships for luminescent millipedes, while B and D are graphs for non-luminescent millipedes.
What did they find?
Results of DNA analysis
The results showed that X.bistipita actually belonged in the Motyxia genus and was renamed accordingly.
The results also seemed to show that bioluminescence only evolved once in all millipede species and is an exclusive characteristic of the genus Motyxia.
Analysing the relationships
In millipedes of the genus Motyxia, there exists a positive linear relationship between the brightness of the millipede’s glow and the distance from the root of the phylogram (A).
A comparable relationship also exists between toxicity and phylogenetic distance (C).
No strong correlations were observed for the non-bioluminescent taxa (B) and (D).
What can we