Ascientist argues that two species of birds are the same species because they have similar body structure, similar dna, and similar beaks because they eat the same food. the birds do have some variations in color patterns and have a different mating season. which piece of evidence would go against this argument and suggest that the birds are actually different species?

Birds have a different mating season this evidence will go against the argument and suggest that the birds are actually different species. Generally, two factors seasonal and behavioral identifies the differences among the species. Species generally interbred among the same population of species according to the season and hence they loose mating opportunities.  Although being sexually compatible they do not interbreed. Behaviorally, a biological clock in species naturally sets breeding cycle according to the resources availability, suitable nesting sites and mating opportunities. Different species have different seasonal requirements to accomplish this.

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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