Ngaba Zadalwa?

Iintsiba Zesikhova

◼ Iinjineli zeenqwelo-moya ziba nomunyu xa zijonga isikhova, intaka yasebusuku. Ngoba? Ngenxa yokuba ayivakali xa ibhabha. INational Geographic Web site ithi: “Le kuphela kwentaka engavakaliyo xa ibhabha.” Yenza njani yona ukuze ingavakali?

Khawucinge ngoku: Ukudlula komoya kwiintsiba zeentaka ezininzi kubangela ukuba zingazinzi emoyeni nto leyo ebangela ingxolo enkulu. Kodwa akunjalo kwisikhova. Iintsiba zaso ezingasemva zinemiphetho ebangela ukuba kungabikho ngxolo, njengoko umoya udlula kwiimpiko zale ntaka. Iintsiba ezingezantsi kumzimba wale ntaka zenza ukuba ingavakali xa ibhabha.

Abayili beenqwelo-moya bangathanda ukufunda okungakumbi ngokungavakali kwale ntaka xa ibhabha ukuze benze iinqwelo-moya ezingavakaliyo xa zibhabha. Izikhululo zeenqwelo-moya eziphantsi kwemilinganiselo engqongqo ephathelele ingxolo zinokukwazi ukuvumela ukufika nokuhamba kwezo nqwelo-moya enoba kusezinzulwini zobusuku okanye kusekuseni. Sele eqalisiwe amalungiselelo okuphucula iinqwelo-moya. UGeoffrey Lilley, unjingalwazi osele esidl’ umhlala-phantsi, osisazinzulu sokuyila iinqwelo-moya kwiYunivesithi yaseSouthampton eNgilani uthi: “Sele siqalile ukukhangela ukuba singaphucula phi na.” Wongezelela athi, kusenokuthabatha amashumi ngamashumi eminyaka ngaphambi kokuba kubekho inqwelo-moya engavakaliyo xa ibhabha.

Ucinga ntoni wena? Ngaba iintsiba zesikhova ezingasemva ezenza ukuba ingavakali xa ibhabha zabakho ngamabona-ndenzile? Okanye ngaba zadalwa?

[Umfanekiso okwiphepha 23]

Jonga iintsiba zesikhova ezingasekhohlo uze uzithelekise nezikakhetshe ezingasekunene

[Inkcazelo Ngemifanekiso ekwiphepha 23]

Long-eared owl: © Joe McDonald/Visuals Unlimited; barn owl sequence: © Andy Harmer/Photo Researchers, Inc.; feather comparison: Courtesy of Eike Wulfmeyer/Wikimedia/GFDL