When using the term 'life form' I assume you are speaking of animals, bacteria, etc. Scientists take years to find their desired conclusion because of how the environment tends to change quite frequently (Depending on where the creature lives). The earth is constantly revolving and rotating, which causes changes in the environment. These changes affect the animals behavior, eating habits, and overall chances of survival. A factor that must also be considered is that scientists have to examine these creatures in their natural habitat which can be an issue depending on where they live. For example, if I were to study the behavioral patterns of a Leopard, it would be extremely difficult to do so because the Leopards are specifically keen at camouflaging in their environment. That would make observing its behavioral patterns very frustrating and time consuming. In a way, mother nature is always against us.
(Hope this helps)
Im pretty sure that if we got all of our energy from the sun then there would be no energy at night so no

No, the arrangement of vascular bundles in the stem same for all plant species.
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☆ <u>In</u><u> </u><u> Monocot </u><u> </u><u>Stems</u></h2>
In monocots, xylem and phloem are organized in vascular bundles scattered throughout the stem. As the plant grows, monocot stems generate new vascular bundles for the new tissue. Monocot stems in general possess a simpler arrangement than that found in dicots.
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☆ <u>
In Dicots</u>
<u> </u><u>Stems</u></h2>
Within the class of plants known as dicots, herbaceous dicots and woody dicots have different arrangements of vascular tissues. In herbaceous dicots (plants, mostly annuals, with soft, non-woody stems), vascular tissue remains in discrete bundles even at maturity. In contrast, when mature woody dicots (plants, mostly perennials, with woody stems) reach maturity, the vascular bundles join together to form continuous rings around the interior of the stem.
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<em><u>ThankYou</u></em><em><u> </u></em>✔✔</h2>