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 The decline is cheetahs throughout their range is mostly due to capture and trade, as well as being hunted for their skins. Historically, they were hunting trophies for Europeans who traveled to Africa in the 1800s. While it is illegal to hunt them today, they are still poached for their skins or captured to be used as exotic pets. Another large contributor to their threatened status is that they face large habitat loss. Urbanization, and agriculture disturb their natural areas reducing their range, so much so that there are now areas of protected land for them, hoping to save the remaining numbers. But they are those that live outside those lands and face conflict with farmers who kill the cheetahs to protect their livestock. Human expansion has also effected the cheetahs food source. In some areas, it is hard for cheetahs to find food, and instead they will try to prey on farmed animals and risk death. A biological contributor to decline is that since the numbers of cheetah are already so low, the chances of inbreeding is higher, making members of a population very close genetically. If a disease were to befall a couple individuals, it could potentially wipeout the entire population in that area. 

    The cheetah (Acinonyx jubatus) is a wild cat found scattered around in small parts of Africa and in Iran. It is famous for being the fastest land animal on the planet, reaching speeds up to 75 miles per hour. There are five subspecies; four that are African and one that is Asian. According to a research paper titled The global decline of cheetah and what it means for conservation by Sarah M. Durant and her team, the cheetah’s historic range was most of Africa (excluding parts of central Africa, Egypt, and Madagascar) and the Middle East into India. Today, cheetahs have lost 98% of their range in Asia, and the Asian Cheetah (Acinonyx jubatus venaticus) is critically endangered with an estimated 50 individuals. In Africa, the remaining four subspecies live only on 13% of the land they once inhabited, causing the Northwest African Cheetah subspecies (Acinonyx jubatus hecki) to also become critically endangered. As of 2014, the known cheetah population is about 6700 individuals over 29 subpopulations (Durant).

The cheetaur is a member of the order Carnivora, family Felidae, and genus Acinonyx. Acinonyx is a genus with only one extant member, the cheetah, and are cats that do not have retractable claws. Cheetaur is the common name for the Acinonyx equuasis. It is named similarly to the mythical centaur (half man, half horse) for its horse-like legs. Their defining features are their long legs and extremely reduced paws with one toe, hence the species name equuasis (“equus” horse). The cheetaur features a mesaxonic foot with a single toed, hairy paw and non retractable claw. The single claw is curved like a hook for better grip on prey. It’s frame is also larger than the standard cheetah. A cheetah stands at about 2.5 feet from the shoulder (Cheetah Facts, 2018). From shoulder to the ground, an adult cheetaur stands at 4 to 5 feet. With these adaptations, the cheetaur is able to run quite fast for longer. The trade offs for longer limbs and larger body mass is that it cannot reach 112 kilometers per hour (70 miles per hour) like those in its genus. It is also not able to easily sneak on prey in areas where the grass is not tall enough. To help it blend in with the grass that is tall enough for coverage, cheetaurs (both male and female) are usually a shade of yellowish brown with dark spots.

    Cheetaur babies are called cubs. Cheetaurs have small litter sizes. The maximum number of babies at a time is two in a litter because of body size of the cub. They reach sexual maturity between one and two years for both males and females. Like other African cats, the females tend to stay with their cubs until they are big enough to fend for themselves while males may live in small groups together. A cub reaches adult size about a year after they are born and can hunt for themselves. Based on its genus, scientist believe the expected lifespan of the cheetaur is about ten years.    

    Other adaptations that they have include having curved ears and facial marking. Their curved ears can rotate slightly to pick up sounds from almost a mile away. The have facial marking like other cheetahs for eye protection from the direct sunlight at the equator (Cheetah Fact, 2018). Since they live in hot, dry areas they have to live around a water source and they will follow prey that do the same. To stay cool, cheetaurs will conserve their energy and will rest for most of the day like other African cats. They will go at great lengths to feed and to escape large lions but other wise like to find shaded areas to rest. 

    Scientists are currently trying hypothesize how exactly a cheetaur would evolve. Some theories include that the cheetah, with their small gene pool and inbreeding, may have introduced mutant genes for toe numbers and leg length. Some of the traits were advantageous for catching fast prey with large stamina and stayed in the gene pool until there was a speciation event where cheetah and cheetaur were almost reproductively isolated from one another. Those with those traits may have thrived and then continued to breed and continue through the years creating the species we know today as Acinonyx equuasis. 

    Like other cheetahs, they live in the grasslands around Africa. The cheetaur is specifically found in Central and Southern Africa. Central Africa grasslands do not receive extreme rainfall but get enough to support tall grasses. The soil is nutrient rich for plants, making them plentiful and a source for adequate nutrition for the grazers (Nunez). With plenty of vegetation, the cheetaur has access to a range of prey animals.  As carnivores, they feed on the deer like animals of the area, for example zebra and antelope. One of its favorite meals is the Steenbok, a smaller species of antelope in Southern and Eastern Africa (Theys). It has horns that can stab a predator, but they are small enough to not cause too much damage to the cheetaur. 

    The cheetaur is a moderately social animal. They do not herd together, as they are already a noticeable predator, but instead will hunt in packs of two or three to bring down larger prey. Since they are larger, the cheetaur can be easily seen by their prey. Hunting in a small group helps to deal with the lack of surprise they can inflict. Their horse like attitbutes allow them to reach speeds of 80 kilometers per hour (50 miles per hour) and can maintain that speed for almost 5 kilometers if needed. Their larger size also make them harder targets for lions that sometimes prey on small cheetahs.

The cheetaur is a member of the order Carnivora, family Felidae, and genus Acinonyx. Acinonyx is a genus with only one extant member, the cheetah, and are cats that do not have retractable claws. Cheetaur is the common name for the Acinonyx equuasis. It is named like the mythical centaur (half man, half horse) for its horse-like legs. Their defining features are their long legs and extremely reduced paws with one toe, hence the species name equuasis (“equus” horse). The cheetaur features a mesaxonic foot with a single toed, hairy paw and non retractable claw. The single claw is curved like a hook for better grip on prey. It’s frame is also larger than the standard cheetah. A cheetah stands at about 2.5 feet from the shoulder (Cheetah Facts, 2018). From shoulder to the ground, an adult cheetaur stands at 4 to 5 feet. With these adaptations, the cheetaur is able to run quite fast for longer. The trade offs for longer limbs and larger body mass is that it cannot reach 112 kilometers per hour (70 miles per hour) like those in its genus. It is also not able to easily able to sneak on prey in areas where the grass is not tall enough. To help it blend in with the grass that is tall enough for coverage, cheetaurs (both male and female) are usually a shade of yellowish brown with dark spots.  

To test if PLCζ was the sole calcium trigger in sperm, Fissore’s team created a PLCζ-null mouse using CRISPR/Cas9. Using CRISPR, they targeted the Plcz1 gene in fertilized mouse eggs. They came up with two strategies as to go about this: Cas9WT with a single sgRNA and Cas9D10A nickase with paired sgRNAs. A line of sperm where Cas9D10A induced a 22 nucleotide deletion in the target area (Plcz1em1Jparr), and another where Cas9WT induced a 17 nucleotide deletion in another area (Plczl em2Jparr) were created. These deletions created two mutant alleles for the Plcz1 gene. When injected into mouse eggs, the mutant cRNA did not induce calcium oscillations confirming that the mutants were PLCζ-null (Plcz1-/-). 

    They found that the loss of PLCζ did not affect the sperms quality or its ability to bind and fuse with an egg. Wild-type sperm (Plcz1+) and Plcz1-/- sperm (Plcz1-) response to progesterone or ionoycin were undistinguishable from each other. When testing the Plcz1+ sperm in wild-type mouse eggs, the sperm induced calcium oscillations “symptomatic of those seen at fertilization in nearly all eggs.” The Plcz1- did not. This was then confirmed with using in vitro fertilization of zone pellucid-free eggs (eggs without a glycoprotein layer around its plasma membrane). 16 out of 34 eggs with Plcz1+ sperm showed Ca2+ oscillations and none of the eggs with Plcz1 em1Jparr derived sperm show any oscillations. His team showed the first direct evidence that PLCζ is the “sole physiological trigger of the Ca2+ oscillations responsible for egg activation in mammals.”

On campus, his lab focus is a continuation of his Ph.D. work with in-vitro fertilization in mammal cells and how exactly sperm begins a calcium released oscillations in the egg. On this topic, he was a part of a paper published in 2017. It is titled PLCζ is the physiological trigger of the Ca2+ oscillations that induced embryogenesis in mammals but conception can occur in its absence. The goal of the study being how exactly sperm triggers calcium oscillations in the egg. This study is important for humans as infertility is a health problem that affects about 1 in 7 couples. The paper stated that in other studies there was evidence that a protein called phospholipase C zeta (PLCζ) trigger calcium release in sperm.

Rafael A. Fissore is a professor and department head at the University of Massachusetts and has been a member of the community for decades. He graduated with a Ph.D. from the university in 1993 in Animal Science. By that time, he had already been a part of a published paper on calcium concentration in bovine (cattle) eggs in 1992. He continued his work with postdoctoral training at Harvard Medical School. The focus there being chemical signals to induce reproduction in animals, one of the signals being calcium. In 2002 he received the CFNR Outstanding Research Award. In 2004, as an associate professor of Animal Science at the University of Massachusetts Amherst, he gave a talk on his fertilization research at the Activated Egg Symposium. He has also filed three patents between early 2003 and mid 2008, by himself and with teams, all towards his field of research in mammalian fertility. 

    Fissore is currently the department head of the Department of Veterinary and Animal Sciences on campus. In 2008, he received a Distinguished Faculty Lecturer honor and the Chancellor’s Medal. He also teaches the honors Animal Science 521: Physiology of Reproduction class. The class focuses on recent studies on cellular and molecular aspects on mammalian fertilization. It also looks at technical and ethical problems when applying new technologies for assisted reproduction and cloning, and how it applies to agriculture, humans, and the natural world. 

Equidae is a family in the order Perissodactyla in class Mammalia. It includes horses, donkeys, zebras, burros, and asses. It also included quagga but they went extinct in 1883. They are in the order Perissodactyla becuase they have an odd number of toes with the center of weight traveling through the 3rd or middle digit. In this case, those in family Equidae have a single functional toe. The single toe, or hoof, makes Equidae the most cursorial, or most adapted for running, Perissodactyla in the modern age. Equidae are grazers meaning their diet consists of grass and they are hindgut fermentors in order to digest grass. They are also polygnous. A single male stallion controls the access to multiple females. The stallions can get agressive and if another approaches, they can bite and kick with their powerful legs to ward them off. 

Evolutionaryly, horses developed in present day North America, Europe, and Asia. They were small, dog sized animals that lived in forests and had more toes. Over time, as the global climate was changing and North America became more grassland, the horses grew in size and reduced the number of digits to adapt. Eventually, modern horses became extinct in the Americas and were not reintroduced until the Europeans travelled there.