```r
g0 <- ggplot(d,aes(x=Lshell,y=BTVolume,colour=Site))
g1<-g0+geom_point()+geom_smooth(method = "lm", se = TRUE)
g2<-g1+geom_point(aes(col=factor(Site)))
g2
```

<img src="qs_21_files/figure-html/unnamed-chunk-82-1.png" width="672" />