From Steve Gettle
“How Crazy is This?” - Giraffe Weevil - Andasibe, Madagascar
Madagascar is filled with unique and interesting things found no where else on earth. This tiny insect is a giraffe weevil it is about 1.5 inches (4 CM) This one is a male, whose neck is roughly three times longer than a female’s. During mating season the males will joust with their necks (much like a giraffe) trying to dislodge their rivals from the vegetation.
Good Luck and Good Light! Steve and Nicole
Image: Giraffe Weevil - Andasibe, Madagascar Nikon Z9, Nikkor 105mm Macro, 1/200th @ f16, ISO 200, Nikon R1 - C1 Macro flash, Image cropped 5% for final composition
Manatees (6) and sloths (5-10) are the exceptions.
It’s very interesting that it is only cervical vertebrae that remain nearly universally consistent. Lumbar and thoracic numbers vary quite wildly.
I found this really interesting paper hypothesizing that a combo of low metabolism and low activity can lead to a loosening of evolutionary constraint on that number, based on the sloths and manatees being the outliers. Their study also shows bushbabies being the only primate where around 30% of the 80ish specimens studied had a thoracic vertebra that had not fully developed a rib, making it much more like a cervical vertebra. They were said to be the least active and metabolically demanding of the primates, further supporting their hypothesis.