Damage to either of these areas can reduce the fitness of the rival, either because of the need to regenerate tissue or because it impairs its ability to detect food.
dˈæmɪdʒ tʊ ˈiːðɚɹ ʌv ðiːz ˈɛɹiəz kæn ɹᵻdˈuːs ðə fˈɪtnəs ʌvðə ɹˈaɪvəl, ˈiːðɚ bɪkˈʌz ʌvðə nˈiːd tə ɹiːdʒˈɛnɚɹˌeɪt tˈɪʃuː ɔːɹ bɪkˈʌz ɪɾ ɪmpˈɛɹz ɪts ɐbˈɪləɾi tə dɪtˈɛkt fˈuːd.