The flexor digiti minimi brevis is a hypothenar muscle in the hand that flexes the little finger (digit V) at the metacarpophalangeal joint. It lies lateral to the abductor digiti minimi when the hand is in anatomical position.
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Features that are common to most "protorosaurs" like Macrocnemus include the ankle having a hooked fifth metatarsal attached to elongated limb elements, with tarsal elements with well-ossified proximal and distal ends. Unlike in Tanystropheus, digit V of the proximal phalanx of Macrocnemus is shorter than the other digits.
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These three muscles form the fleshy mass at the base of the little finger, and are solely concerned with the movement of digit V. The other two muscles that make up the hypothenar muscle group are the abductor digiti minimi and the opponens digiti minimi. In anatomical position from medial to lateral is the abductor digiti minimi, flexor digiti minimi brevis, and opponens digiti minimi.
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This articulation creates a virtually immobile joint between the two. Petrolacosaurus has a phalangeal formula for the manus of 2-3-4-5-3. For the pes, the formula is 2-3-4-5-4. The digits increase in length from digit I-digit V. Metatarsal IV is 3.5 times as long as metatarsal I. Many lines of post-Paleozoic reptiles have a reduction in digit IV in the manus and pes, indicating that Petrolacosaurus is more primitive than those reptiles.
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Gwyneddichnium corresponds to footprints from a quadrupedal animal with a small pentadactyl (five-fingered) manus (hand) and a notably larger five-toed pes (foot). The manus and pes are mesaxonic, meaning that the third digit is the longest digit, followed by the subequal second and fourth digits. The innermost digit (digit I) and the outermost digit (digit V) were short and located close to the rest of the foot. Sometimes the small fifth digit is poorly preserved, making the hand or foot appear to be tetradactyl (having only four digits).
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This was further supported by Benedetto in 1973, who named for the taxa the new family Herrerasauridae, which he classified as saurischians, possibly within Theropoda but not in Sauropodomorpha. However, in 1977 Galton proposed that Herrerasauridae only included Herrerasaurus, and found it to be Saurischian incertae sedis. Proposed in 1987 by Brinkman and Sues, Herrerasaurus has at times been considered basal to Ornithischia and Saurischia, although Brinkmann and Sues still considered it to be inside Dinosauria. They supported this on the basis that Herrerasaurus has a large pedal digit V, and has a well developed medial wall on the acetabulum.
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The flexor digiti minimi brevis arises from the hamulus of the hamate bone and the palmar surface of the flexor retinaculum of the hand. It is inserted into the medial side of the base of the proximal phalanx of digit V. It is separated from the abductor digiti minimi, at its origin, by the deep branches of the ulnar artery and the ulnar nerve. The flexor digiti minimi brevis is sometimes not present; in these cases, the abductor digiti minimi is usually larger than normal. The flexor digiti minimi brevis is one of three muscles in the hypothenar muscle group.
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Life restoration of a polydactylous hupehsuchian based on SSTM 5025 In late 2003, a new specimen of hupehsuchian called SSTM 5025, found from the same area as Hupehsuchus and Eretmorhipis, was briefly mentioned in the journal Nature. It is most notable for exhibiting polydactyly, in which more than the usual maximum of five digits per limb were seen as in most advanced tetrapods. Polydactyly is also seen in ichthyosaurs. However, in ichthyosaurs, this condition occurs as either bilateral polydactyly in the case of ophthalmosaurids (extra digits anterior to digit I and posterior to digit V) or interdigital or postaxial phalangeal bifurcation as in non-ophthalmosaurids.
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Later, with the introduction and evolution of crash pads, climbers were able to push the limits of highball bouldering ever higher. In 2002 Jason Kehl completed the first highball at double-digit V-difficulty, called Evilution, a 55-foot (16.8 meter) boulder in the Buttermilks of California, earning the grade of V12. This climb marked the beginning of a new generation of highball climbing that pushed not only height, but great difficulty.It is not unusual for climbers to rehearse such risky problems on top-rope, although this practice is not a settled issue. Groundbreaking ascents in this style include; Ambrosia, a 55-foot (16.8 meter) boulder in Bishop, California, climbed by Kevin Jorgeson in 2015 sporting the grade of V11.
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