Category: Uncategorized

NOT DESIGNED FROM SCRATCH. "The origin of our feet dates back to lobe-finned fishes, and has evolved into five-rayed, weight supporting structures since." https://lnkd.in/esuQhhw View in LinkedIn

PANDA'S THUMB. "Botched jobs are common, in fact. The classic example is the panda’s thumb, which it uses to grasp bamboo. “The panda’s true thumb is committed to another role. So the panda must…settle for an enlarged wrist bone and a somewhat clumsy, but quite workable, solution,” wrote Stephen Jay Gould in 1978." https://lnkd.in/dv-JiV6 View in LinkedIn

PATCHED TOGETHER. "The eyes of many taxa record their evolutionary history in their imperfect design. The vertebrate eye, for instance, is built "backwards and upside down", requiring "photons of light to travel through the cornea, lens, aqueous fluid, blood vessels, ganglion cells, amacrine cells, horizontal cells, and bipolar cells before they reach the light-sensitive rods and cones that transduce the light signal into neural impulses, which are then sent to the visual cortex at the back of the brain for processing into meaningful patterns." https://lnkd.in/decez8M View in LinkedIn

NUMEROUS SIMILAR INVENTIONS. "Certain components of the eye, such as the visual pigments, appear to have a common ancestry: that is, they evolved once, before the animals radiated. However, complex, image-forming eyes evolved some 50 to 100 times – using many of the same proteins and genetic toolkits in their construction." https://lnkd.in/dgxtAku View in LinkedIn

IMMUNE SYSTEM. "In a fascinating inversion of this view of life, however, recent studies have shown that an individual's immune system is in part created by the resident microbiome. In vertebrates, the gut-associated lymphoid tissue is specified and organized by bacterial symbionts. The immune system does not function properly and its repertoire is significantly reduced when symbiotic microbes are absent in the gut." https://lnkd.in/ddVyNR5 View in LinkedIn

"THE EYE of the Trilobite was already highly sophisticated by Cambrian time - yet, it was hardly a perfect design - rather, it resulted from the tinkering of natural selection on the genomic ingredients that already existed." https://lnkd.in/dfRbEgj View in LinkedIn

INTERSPECIES MERGERS. "Animals can no longer be considered individuals in any sense of classical biology: anatomical, developmental, physiological, immunological, genetic, or evolutionary. Our bodies must be understood as holobionts whose anatomical, physiological, immunological, and developmental functions evolved in shared relationships of different species." https://lnkd.in/ddVyNR5 View in LinkedIn

IMPACT ON ADAPTION. "Convergent evolution of gene expression via the insertion of transposable elements also suggests that such transposons can mediate adaptive evolution. The selective silencing of such transposons by DNA methylation or small interfering RNAs appears to be another policing mechanism that has facilitated evolution." https://lnkd.in/ddVyNR5 View in LinkedIn

INSOURCED GENES DRIVE UTERUS. "The emergence of the uterus, the defining character of eutherian mammals, appears to have been facilitated independently in several mammalian families by transposons integrating into the regions controlling the expression of the prolactin gene. These transposons contain transcription factor binding sites that enable the prolactin gene to become expressed in the uterine cells." https://lnkd.in/ddVyNR5 View in LinkedIn

PARASITIC OR NEW TOOL? "Although much of this added DNA is thought to be “parasitic,” some transposable elements may have been critical in creating new patterns of transcription." https://lnkd.in/ddVyNR5 View in LinkedIn