Skip to main content

convergent E

 Both the "anteater" and "crab" forms are famous examples of convergent evolution, where unrelated species independently evolve similar body plans to adapt to similar environmental pressures. The anteater body plan has evolved more often in a shorter time frame than the crab body plan. 

https://phys.org/news/2025-07-mammals-evolved-ant-eaters-dinosaur.html

https://www.science.org/content/article/things-keep-evolving-anteaters-odd-animals-arose-least-12-separate-times


Anteater Evolution (Myrmecophagy)

  • Frequency and Speed: The myrmecophagy (ant- and termite-eating) body plan has evolved in mammals at least 12 separate times since the extinction of the dinosaurs 66 million years ago.
  • Lineages: This adaptation has appeared across all three major divisions of mammals: placentals (like giant anteaters, aardvarks, and pangolins), marsupials (numbats), and monotremes (echidnas).
  • Driving Force: The primary driver is the immense abundance of ants and termites, which represent a massive, globally distributed food source. The long snout, sticky tongue, and powerful claws are effective solutions for accessing this resource.
  • Evolutionary Path: This is considered an evolutionary "one-way street" because the specialization makes it difficult to revert or change to another diet. 
Crab Evolution (Carcinization)
  • Frequency and Speed: The crab-like body plan (carcinization) has evolved at least five separate times within different groups of decapod crustaceans over a couple of hundred million years.
  • Lineages: This process occurs within the broader group of crustaceans, turning creatures like hermit crabs and squat lobsters into "imposter crabs" with a true crab form.
  • Driving Force: The compact, armored, and broad body with a tucked abdomen provides significant survival advantages, including better defense, stability in water, agility in crevices, and protection from predators.
  • Evolutionary Path: This design is highly effective for marine and some terrestrial environments, leading to its recurrent emergence in different lineages. 
Summary Comparison
Feature Evolution into AnteaterEvolution into Crab
Scientific NameMyrmecophagizationCarcinization
Times OccurredAt least 12 timesAt least 5 times
Time Frame~66 million years~200 million years
Groups AffectedAcross all major mammal divisionsWithin different decapod crustacean groups
Reason for SuccessExploiting the abundant ant/termite food sourceOptimized body plan for defense and agility in specific habitats
In short, while the idea of everything becoming a crab is a popular internet meme, the evolution into an anteater body plan is a more frequent and rapid occurrence in the history of mammals
Labels:

Comments

Post a Comment

Popular posts from this blog

7 WAYS for achieving your purpose

 CHOOSE YOUR DIRECTION make use of free will.   Jesus and the blind man. Why does Jesus ask him what he wants when it is obvious he want to see? Choose area (learning, marriage, finance, friendships) of importance to you, and make 3-10 goals. What measurable  and compelling goal is possible? Set the goal, and then you have the direction. Reticular activating system: it helps you find whatever you are focusing on.  E.g. Search for blue items. Okay, how many purple items are there? you don't know. Because you only focus on what you look for. Your brain gets excited and get power the moment it knows what direction it is about to take. Decide  your exact deadline when you will achieve it. Also, ascertain what you want to sacrifice . (time/money/patience/difficult situations) The price will be  "Where there is no vision, people perish"-Solomon  CHOOSE YOUR REASONS Do you have insight to yourself? Be a person of deep water, look deeper. Introspect. What...
Post a Comment
Read more
  A quiet place Lit umbrella Empty at times At others Tripping with wires White light Once Bright burning flavescent Yellow and crumpling in its notes. Then the umbrella folds. Another takes its place. Life in the Dark Room.
Post a Comment
Read more

Conflating the liberty of freedom and burden of choice, and finding the balance in between

"...the individual ceases to be himself; he adopts entirely the kind of personality offered to him by cultural patterns; and he therefore becomes exactly as all others are and as they expect him to be...The person who gives up his individual self and becomes an automaton, identical with millions of other automatons around him, need not feel alone and anxious any more. But the price he pays, however, is high; it is the loss of his self." -Escape From Freedom by Erich Fromm, first published by Holt, Rineheart and Winston, New York, 1941. http://www.alternativeinsight.com/Escape_from_freedom.html and then comes the question many strive to answer; what do we risk to lose when we are already in an individualised state of mind? Even more, i think. The attraction of the self makes it even harder to conform, whilst the pressure for conformity never ceases—in fact the pressure exponentially increases—staring you down through that bright screen all day and for most of the night. Freedo...
Post a Comment
Read more