“…They are comparable to acuities reported for kittens (Mitchell, Giffen, Wilkinson, Anderson, & Smith, 1976), cats (Smith, 1936), sea lions (Schusterman & Balliet, 1971), 5-month-old human infants (Fantz, Ordy, & Udelf, 1962), and about one fifth of that reported for adult humans (Spence, 1934).…”