For a recently discovered species of marsupials, the Black-tailed Antechinus, it seems that parenthood is the highest cause of death. The Black-tailed Antechinus was discovered in Queensland’s Springbrook National Park, Australia by Dr. Andrew Baker. He laid 300 traps of oats and peanut-butter to catch the marsupial. After putting the marsupials through a multitude of tests they found that all the males died after mating. The stress hormone levels in the males, post mating, would steadily increase until eventually the males bodies would simply shut down. In this species of marsupials the males never live to see their young be born.
A study conducted by a team of researchers from the University of California, Riverside, Indiana University, Purdue University, Fort Wayne, and George Washington University showed that lizards from islands are more calm then ones from mainland regions. The researchers established this by comparing the flight initiation distance, or distance before a prey starts to flee when approached, between various lizards. The researchers were able to approach island lizards more closely then mainland lizards. The study was inspired by a long-time debate that island animals were more “tame” that started with an observation by Charles Darwin when he visited the Galapagos Islands. He felt that because these islands were scarce of most predators, those animals which did not waste energy fleeing unnecessarily would have a better chance of survival. All of this being said the findings were inconclusive.There are many variables that factor in to flight initiation distance and can not be categorized by where a creature lives.
Recent research done by by biologist’s Catherine Peichel and Clifford Tabin show that the complex actions that are required by fish that travel in Schools. Fish that travel in schools do so to better protect themselves from predators, but swimming in a school requires an enormous amount of synchronization in body patterns and the ability to the change with water currents and other environmental changes. The first study conducted by Peichel in which she gathered Sticklebacks that were prone to joining schools and those that were not, showed differences in certain genetic regions. This suggests that the act of traveling in a school is not stored in memory, but is stored in their genetic make up. Research done by Tabin suggests that the eyes are a huge part of Schooling. He found that blind Sticklebacks dwell deep underwater in solitude while the others travel in their schools. This research relates to whether Humans are driven to stay in packs and be around each other because of these certain genetic regions, or whether we as people were brought up this way.