Paenungulata sub ungulates Hyracoidea hyraxes Sirenia manatees and sea cows Proboscidea elephants Strong DNA Similarity Hyraxes most likely sister taxon to Proboscidea Sirenia Tethytheria Morphological synapomorphies all paenungulates Fancy tongue muscle split styloglossus Long pre sacral vertebral column Paired mammary glands and teats located behind forelimbs 4 teats near groin in hyraxes Big animals slow down metabolism due to large size Few if any predators this is what allows you to slow metabolism down Hyracoids elephants Toenails Sensitive pads on feet can sense vibrations Deep lower jaw for grinding Good memory Tusks Hyracoidea Family Procaviidae hyraxes dassies coneys 3 genera and 11 species Africa and Middle East Earliest fossils from Eocene of Morocco Diverse in Paleogene runners climbers Diversity declined in Miocene Dendrohyrax browser south of Sahara Procavia Heterohyrax grazers mid East open areas S of Sahara 7 month gestation 1 2 young litter Herbivorous cecal fermentation plant feeding Prefer rocky outcrops trees for Dendrohyrax Diurnal with polygynous family groups Diurnal active during the day Name for organisms active during twilight times of day crepuscular Use behavioral thermoregulation basking Sweat through feet Body is covered in fur so they may be able to do it that way since there s no fur Hyracoidea teeth Incisors ever growing Diastema No canines Enamel on anterior of incisors as in rodents Pectinate comb like lower incisors Why Cleaning each other Hyracoidea feet Four toes on forefeet three toes on hind feet Feet mesaxonic large toe is central Digits of pes bear flattened nails except clawed second digit Cavies guinea pigs Rodentia South america Family Caviidae Hyracoids converge with cavies Incisors diastema and cheek teeth lophodont ridges Dendrohyrax Soles of feet naked glandular secretions keep soles moist How is this beneficial Suction cup Low crowned molars and premolars Arboreal browsers Surprisingly agile in trees Heterohyrax yellow spotted rock hyrax Procavia rock hyrax share outcrops and nurseries mixed group of young Live in rocky outcrops in arid grassland Form large colonies dominant males defend a group of females Procavia Nest among the rocks graze alongside Double cecum How would that inform you about how they live You can go for plant food that most other organisms won t be able to breakdown Sirenia Dugongs and manatees Completely aquatic herbivores 2 genera and 4 species Weights above 1500 kg Nearly hairless thick skin Nostrils valvular Why need them if you aren t a fast swimmer Slow metabolic rate so it helps conserve energy Thick dentary bone Middle ear bones are massive Provide you with the low frequency communication Dense heavy bones provide ballast Less predation Five toes manus enclosed in flipper Pelvis vestigial hind limbs absent Tail is horizontal fluke Desmostylian Paleoparadoxia Pacific Rim 20 10 MYA Prorastomus early Eocene of Jamaica Still capable of terrestrial locomotion Sirenia teeth Cheek teeth columnar Covered with cementum dugongs or enamel manatees Tooth replacement as in elephants back to front conveyor belt why Takes time to grow so you need them right away Probs eating sea grass easy chewing material Inhabit coastal seas large rivers and lakes Sirenia Slow moving grazers Slow metabolism and little body fat Restricted to warmer waters Lek mating arena Alpha male will be most successful and mate with the most females Beta male not very successful Gamma male may not breed at all Sneaker males swerve in and mate with female while other males are fighting Make complex sounds Long lived with low reproductive rate