Bayan haka, sai a amsa tambayar a cikin wannan harshe: Passage: Wasu nau'ikan, da ake kira nau'ikan keystone suna samar da cibiyar tallafi ta musamman ga tsarin halittun su. Rashin irin wannan nau'in yana haifar da rushewar aikin tsarin halittu, da kuma asarar nau'ikan da ke wanzuwa. Nau'ikan Keystone galibi masu farauta ne saboda ikonsu na sarrafa yawan ganima a cikin tsarin halittun su. An nuna mahimmancin nau'ikan keystone ta hanyar lalacewar saniya ta Steller (Hydrodamalis gigas) ta hanyar hulɗarta da otters na teku, urchins na teku, da kelp. Kelp beds suna girma kuma suna samar da ɗakunan yara a cikin ruwa mai zurfi don samar da halittu waɗanda ke tallafawa sarkar abinci.
ƙwararrun ƙwararrun ruwa