Alcuni batteri presenti nell’intestino umano sono vecchi di almeno 15 milioni di anni. Questa la conclusione di uno studio apparso in questi giorni, realizzato da ricercatori dell’Università della California a Berkeley e pubblicato sulla rivista Science.
La scoperta suggerisce che l’evoluzione della specie umana gioca un ruolo decisamente più importante rispetto a quanto si potesse pensare, soprattutto nella composizione batterica intestinale. I batteri contribuiscono allo sviluppo dei primi stadi dell’intestino dell’uomo e portano il sistema immunitario a combattere agenti patogeni.
I ricercatori hanno quindi individuato prove genetiche di un’evoluzione differenziata di questo tipo di batteri nell’uomo e nelle grandi scimmie malgrado le due specie avessero un origine comune.
ATS/AFP/Swing
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