unexpected input in rpart

Hi all, I'm a newbee using R. I need to do a classification tree using the
rpart package. Basically I have a set of birds of known sex and several
morphological measurements and we want to predict the sex using the
morphology. I read my csv file and it shows up in R no problem, looks fine
but when I execute the following rpart command 

hawkadults_rpart<-rpart(Sex?Footpad+Mean_2ndlength+Bill_length+Tarsus_reg+Mass+Wing_chord,method="class",data=hawkadultsDF)

I get the message Error: unexpected input in "hawkadults_rpart<-rpart(Sex?"

I feel like as a newbee I'm missing something rather obvious. Any and all
help would be greatly appreciated.

Thanks

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