Duk da yake sun bar jaka a cikin kwanaki 105 bayan haihuwa, suna bayyana a matsayin ƙananan kwafin iyaye kuma suna auna kimanin 200 grams (7.1 oz). Masanin ilmin dabbobi Eric Guiler ya rubuta girmansa a wannan lokacin kamar haka: tsawon rawanin-snout na 5.87 cm (2.31 in), tsawon wutsiya na 5.78 cm (2.28 in), tsawon tsawon 2.94 cm (1.16 in), 2.30 cm (0.91 in), shank 4.16 cm (1.64 in), 4.34 cm (1.71 in) da kuma rawanin-rump yana da 11.9 cm (4.7 in). A wannan lokacin, aljanu suna tsawaita a cikin layi mai tsawo. Bayan an fitar da su, jaririn aljanu ya kasance a waje da jaka, amma sun kasance masu zaman kansu a cikin tsofaffin jarirai kuma suna kimanin kimanin 200 grams (7.1 oz).
a waje da jakar