Insectpestsareamongtheleadingcausesofcropfailure.
A、expectedIn1861itseemedinevitablethattheSouthernstateswouldbreakawayfromtheUnion.
Bats fly, rather than glide, and thus are the only mammals capable of true flight.
ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
Incalculatingthedailycalorierequirementsforanindividual,variationsinbodysize,physicalactivity,andageshouldbetakenintoaccount.
Someseaurchins海胆havevenomous(toxin)spines
