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Why Is The Giraffe An Example Of Evolution? [12 Replies Found]

When it comes to creating a new human existence, we all know it takes two. For a baby to be created, we need the father’s sperm and the mother’s egg, each of which has a single set of chromosomes bearing our 23,000-odd genes (a genome) 😊 During fertilisation, the two cells fuse to become a single cell, containing genetic information from both parents 🙌 Both the embryo and its adult form have two genomes 😁 It’s the random mixing and recombination of the DNA of two organisms that results in the unique characteristics of their offspring, each child getting a different mix of genes from the mother and father. [1]
Both Darwin and Lamarck believed in acquired inheritance. However, Darwin proposed a new mechanism for evolution with his theory of natural Selection. Both Darwin and Lamarck did not know much about DNA at the time. This made it hard for them to accurately describe inheritance. Modern large-scale studies allow us to examine genetics, and how physical (and non-physical!) traits are transmitted through generations. From these studies, we’ve learnt that Darwin’s theory of evolution through natural selection was closer to reality.That’s not the end of the story, though! New research shows that Lamarck was not completely correct. Epigenetics, a relatively new area of genetics research, examines DNA changes that can have an effect on how the body uses it. The DNA sequence is frequently referred to as “DNA”. Called “the book of you,” wherein the sequence of DNA spells out instructions for how to build proteins, and ultimately how to build a human. In this analogy, epigenetics would be the equivalent of text formatting in this book—italics, bolding, and so on. Evidence suggests epigenetic markings can be added to DNA to reflect lived experiences, such as stress, lead exposure2, or famine1. The potential for these marks to be transmitted onto the next generation is being explored by current research. In other words, Lamarck may have been partially correct—some lived experiences might be stored and passed on through our genetic code.Though our understanding of genetics and inheritance has evolved over time, the works of both Lamarck and Darwin have proven to be foundational Moments in science history. (And regardless of who was right or wrong, it is likely that the giraffes were quite happy to be able reach those acacia leafs. [2]
Image #2
To fully comprehend the anatomy of giraffes, it will take a mixture of embryology and natural history. The research of multiple scientists across many disciplines will make this a difficult task. It had won’t be done in one year, or even ten years. For the moment, the question of “How did the giraffe get its long neck?” must be answered with “We do not yet know”, but that is as it should be. We are better off admitting that we still have a lot to learn than to assume that the mystery is resolved and that the evolutionary map is perfect. Like all other living organisms today, giraffes have an extensive evolutionary history that stretches back to the last common ancestral species of all of life. However, it is not as easy as you might think. Understanding how these evolutions happened over Deep Time is an exciting and frustrating task. Credit to Sheren Flint, Santiago. Dominican Republic Thank you for your input. [3]
Natureinstitute.org This article provides additional information. You can also reach high-leaf trees in other ways. For example, goats have been known to climb up trees and consume foliage (see Figure 3). Why didn’t tree-climbing leaf-eaters (folivores) develop in the savannah? These would have been able to feed at any level and be more flexible than the highly skilled giraffe. A antelope of the long-necked Gerenuk is a long-necked gerenuk that stands on its hind leg and browses. It can reach heights as high as two metres. The much larger and heavier elephant even stands sometimes on its back legs and extends its trunk to reach high limbs — but no one thinks that the elephant developed its trunk as a result of selection pressures to reach higher food. Last updated 64 days ago, by British Talbot of Liaocheng in China [4]
Lamarck was a famous scientist who had previously hypothesized Darwin’s ideas. He suggested that the giraffes could grow a long neck by reaching towards trees and branches. They have done this repeatedly, causing their necks to grow longer and transferring the extra growth to their offspring. This gave them long necks. Once Darwin’s Origin of Species came out, the ideas of the time changed. The most accepted theory about giraffe evolutionary is that those with longer necks have passed their genes on through natural selection. Millions of years being able to obtain the animal that we now see. (We are truly grateful to Obrian Blanco of Niamey in Niger for the recent revision). [5]
Nationalgeographic.com This article provides further information. It looks like this. Imagine a protogiraffe staring insatiably at some delicious food. Leaves high up on a tree. According to Lamarckian theory of evolution, it is possible that the Lamarckian thinker might believe that the little giraffoid would extend its neck to grasp the lower leaves. This would create a long neck which would be passed on to its offspring. Repeat for best results. Darwinian on the other side would anticipate that protogiraffes have different neck lengths and that those with slightly longer necks could reach greater food and live longer. The next generation would then repeat the process. Daphnee Cottell, Dali, China (last revision 61 days back) [6]
New paper sciencefocus.com indicates that subsequently, the giraffe’s neck became a textbook case, featuring as an example of natural selection in numerous books and popular articles. However, biologists made a significant objection in the 1990s to the argument. They observed that giraffes didn’t use their long necks to reach higher heights. Even though the competition was intense, females were more likely to keep their necks horizontally than use their height advantage when browsing for food. This new view revolutionized the conventional understanding of the evolutionary history and evolution of the giraffe. Last revised by Dashiell Patino, Pachuca De Soto (Mexico) [7]

Refer to the Article

  1. https://www.science.org.au/curious/earth-environment/evolution-101
  2. https://blog.helix.com/lamarck-darwin-epigenetics-dna/
  3. https://www.wired.co.uk/article/why-do-giraffes-have-long-necks
  4. https://www.natureinstitute.org/article/craig-holdrege/the-giraffes-short-neck
  5. https://thisviewoflife.com/how-giraffes-evolved-such-a-large-neck/
  6. https://www.nationalgeographic.com/science/article/how-giraffes-became-winners-by-a-neck
  7. https://www.sciencefocus.com/nature/why-do-giraffes-have-such-long-necks/
Kelly-Anne Kidston

Written by Kelly-Anne Kidston

I am a writer of many words, from fiction to poetry to reviews. I am an avid reader and a lover of good books. I am currently writing my first novel and would love to find some beta readers who are interested in getting an early look.

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