Mammal-Avian Inversion Duality Hypothesis
Inversion in evolutionary developmental biology is a theory that antropoid structures along the dorsoventral (DV) axis adapted an orientation opposite to the ancestral mammal form. The hypothesis that the DV axes of protostomes and chordates are inverted is supported by molecular biology research. Evidence from the genome analysis involved in establishing the DV axes in the two groups shows that the genes are also inverted. Invertebrate chordates also have structures that are inverted. Ascidian larvae have a dorsal mouth.
Inverted Morphological Characteristics of
Mammals-Birds include the following
1. DNA: XY male and WZ female
2. Esophagus and Intestines
3. Legs and Wings
4. Respiratory and Digestive System
5. Avian nucleated red blood cells (RBC)
6. Male organ erected by lymph & WBC
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10. 11. 12. 13. 14. 15. 16. 17.18. 19. 20. 21.
Birds: Are they Dinosaurs in Disguise or Inverted Mammals?
Paleontologist acquainted with the phylogeny of vertebrates tell us that birds evolved from dinosaurs. They say that birds are avian dinosaurs. Other dinosaurs are called non-avian dinosaurs. Technically speaking they say that birds are really reptiles. The open question was how cold-blooded creatures evolved into warm-blooded ones!
New evidence published by University of Adelaide researchers asserts that dinosaurs were warm-blooded like birds and mammals and not cold-blooded like reptiles as commonly believed. In a 2013 paper in PLoS ONE, Roger Seymour of the University's School of Earth and Environmental Sciences, argues that dinosaurs, if cold-blooded, would not have the muscular power to prey on other animals and dominate over mammals as they did throughout the Mesozoic period.
There are also numerous skeletal resemblances between birds and reptiles. Bones are used to establish the connection between birds and dinosaurs because bones are the main features preserved in fossil records. There is a gap in the Late Jurassic fossil record of the first known bird and the Early Cretaceous dromaeosaurs, characterized as the probable sister group of birds. The other reason for the link between birds and dinosaurs is probably because no other suitable candidates for avian ancestors have been found.
The first birds shared skeletal characteristics with Coelurosaurian Dinosaurs which included the following.
- Pubis (one of the three bones making up the vertebrate pelvis) shifted from an anterior to a more posterior orientation and bearing a small distal "boot".
- Elongated arms and forelimbs and clawed manus (hands).
- Large orbits (eye openings in the skull).
- Flexible wrist with a semi-lunate carpal (wrist bone).
- Hollow, thin-walled bones.
- 3-fingered opposable grasping manus (hand), 4-toed pes (foot); but supported by 3 main toes.
- Reduced, posteriorly stiffened tail.
- Elongated metatarsals (bones of the feet between the ankle and toes).
- S-shaped curved neck.
- Erect, digitigrade (ankle held well off the ground) stance with feet positioned directly below the body.
- Similar eggshell microstructure.
- Teeth with a constriction between the root and the crown.
- Functional basis for wing power stroke present in arms and pectoral girdle (during motion, the arms were swung down and forward, then up and backwards, describing a "figure-eight" when viewed laterally).
- Expanded pneumatic sinuses in the skull.
- Five or more vertebrae incorporated into the sacrum (hip).
- Straplike scapula (shoulder blade).
- Clavicles (collarbone) fused to form a furcula (wishbone).
- Hingelike ankle joint, with movement mostly restricted to the fore-aft plane.
Mr. Ostrich:
"Did we evolve from Dinosaurs?"
"What's an ADIM?"
Ms. Emu:
"No! We are ADIMs"
"A Dualogically Inverted Mammal."