Error in pic(independent, tree) :
  missing data in 'x': you may consider removing the species with missing data from your tree with the function 'drop.tip'.

library(ape)
library(geiger)
library(nlme)
library(phytools)

data <- read.csv("App and ADW-Museum Ecology Data.csv", row.names=1)
tree <- read.nexus('c://users/user/documents/formated zelditch.nex')

td = treedata(tree, data, warnings=FALSE)
tree = td$phy
data = td$data

dependent <- data[,"chroma"]
independent <- data[,"mass..Pantheria."]

names(independent) <- names(dependent) <- rownames(data)
dependent <- pic(dependent, tree)
independent <- pic(independent, tree)

model <- lm(dependent ~ independent - 1)
print(summary(model))

library(ape)
library(geiger)
library(nlme)
library(phytools)

data <- read.csv("App and ADW-Museum Ecology Data.csv", row.names=1)
tree <- read.nexus('c://users/alec/documents/formated zelditch.nex')

td = treedata(tree, data, warnings=FALSE)
tree = td$phy
data = td$data

dependent <- data[,"chroma"]
independent <- data[,"mass..Pantheria."]

names(independent) <- names(dependent) <- rownames(data)

for (name in rownames(data)) {

    if(is.na(dependent[name])) {
      drop.tip(tree, name)
  }

  if(is.na(independent[name])) {
      drop.tip(tree, name)
  }
}


dependent <- pic(dependent, tree)
independent <- pic(independent, tree)

model <- lm(dependent ~ independent - 1)
print(summary(model))