Butterflies also act as a lower member of the food chain. They are a hearty meal for a number of animals, including birds and mice. As populations of butterfly diminish, so will populations of birds and other animals that rely on them as a food source.
The conus medullaris (Latin for medullary cone) is the tapered, lower end of the spinal cord.It occurs near lumbar vertebral levels 1 (L1) and 2 (L2), occasionally lower. The upper end of the conus medullaris is usually not well defined.After the spinal cord tapers out, the spinal nerves continue to branch out diagonally, forming the cauda equina.onus medullaris syndrome is a collection of signs and symptoms associated with injury to the conus medullaris. It typically causes back pain and bowel and bladder dysfunction but weakness and sensory loss is uncommon.
Conus medularis, the spinal cord ends at the level of L1 -L2 (lumbar vertebrae) in an average adult this distal most part is called conus medularis. It contains sacral segment of the spinal cord i.e S1-S5. The nerve root value for ankle jerk is S1, S2 whereas the nerve root value for knee jerk is L2, L3, L4. Hence any lesion or compression in the conus medularis cause only affects ankle jerk not the knee jerk. Edit 1:Conus medularis can be of two type, with lumbar nerve root involment or without lumbar nerve root involment.