True, a lot of cultivated fields use fertilizers that can be harmful to fish
Answer:
<em>Hox </em>Gene
Explanation:
First, you're question is very vital, there are many ways in classifying along with identifying all living organisms that includes; morphological analysis, molecular systematics (studying the similarities and differences of the genetic data such in the sequences of DNA, RNA, and rRNA ), homology, cladistics, etc. based on phylogenetic tree, which the study of the evolutionary among various species.
But through it said that all living organisms shared one common ancestor. However, what makes them different from one to another is the homeotic genes that called <em>Hox </em>Genes; which specify the fate of a particular segment or region of the body, meaning the number and arrangements of the<em> Hox</em> genes varies considerably among different types of animals.
For instance, Sponges have at least one homologous to<em> Hox</em> genes, also insects have nine or more <em>Hox </em>genes resulting in multiple <em>Hox </em>genes occur in a cluster in which the genes are close to each other along a chromosome. Therefore, increases in the number of<em> Hox</em> genes have been instrumental in the evolution of many animals species with greater complexity in body structure.
Overall, more <em>Hox</em> genes, more complexity in body structure resulting in the differences of their morphological structure.
Hope that answered your question!
He did not take in to account for wind currents and the fact that CO2 or the carbon stays in the air
The answer to this question would be: increased food height
Giraffe becomes tall because its food height is increased. In this case, the environmental pressure on Giraffe would be the increased height of the food.
The taller giraffe has access to higher food. Then, the giraffe with the higher chance of survival in this scenario would be the giraffe with a taller height.
I think the answer is liver and hepatic portal vein
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