ðɪs ɪz ˈɛvɪdənt fɹʌmðɪ ɑːbzɚvˈeɪʃən ʌv ʃˈæloʊ, ˌeɪsɪmˈɛtɹɪkəl ɹˈɪdʒᵻz dᵻvˈaɪdᵻd ˌɪntʊ tˈuː pˈɑːɹts baɪ ɐ fˈaɪn ɡɹˈuːv.
This is evident from the observation of shallow, asymmetrical ridges divided into two parts by a fine groove.