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Biology 2013 past paper question -

The group of birds, known as warblers, contains many species which are very similar in external appearance. The chiffchaff, Phylloscopus collybita, and the willow warbler, Phylloscopus trochilus are two species of warbler. These warblers are so similar that many experts can identify them only by listening to their characteristic songs. Their songs are used during breeding to mark territory and attract mates.

Question: Explain how these two types of warbler became separate species

Mark scheme:
1. idea of geographical isolation ;
2. idea of different {environmental conditions /
habitats / eq} ;
3. reference to different selection pressures ;
4. idea that mutation resulted in {adaptation
/ increased survival} ;
5. idea of {decrease in gene flow / different
alleles} ;
6. ref to reproductive isolation ;
7. credit suitable example e.g. different
songs, incompatible genitals ;

I dont understand the mark scheme. Even by looking at it idk what to answer
so here the topic is about speciation. So first the population is diverse meaning it has many different alleles some brought about by mutation.
then due to some event the population becomes separated into two groups. each group has different allele frequencies and due to the differing environments, they too have different selection pressures which leads to natural selection. different alleles are favoured over others. this occurs over many generations until the two individuals from each population cannot interbreed to produce fertile offspring.

just go on youtube and search up Miss Estruch and go to the speciation video for help
i died trying to understand the question
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Avatar for zarahh09
zarahh09
OP
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Original post by SUpershaf786
i died trying to understand the question

same lol

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