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The free-living, stalkless comatulids make up the bulk of living crinoid diversity and are the only crinoids remaining in shallow water, but compared to the stalked crinoids their fossil record is fragmentary and understudied, especially outside Europe. We present new Albian fossil comatulids from the Glen Rose Formation, central Texas, and study them using computed tomography, scanning electron microscopy, morphometry, and cladistic analysis of discrete and continuous characters. New material comprises the previously described Decameros wertheimi and Semiometra klari? and the new taxa Semiometra alveoradiata n. sp. and an extremely unusual new form Castaneametra hodgesi n. gen. n. sp. In addition to being exceptionally variable, this species is the largest known comatulid, has the most cirri of any known comatulid, and exhibits unique architectural features and voluminous, through-going coelomic cavities. We reconstruct its paleobiology, infer its phylogenetic affinities, argue for its origin from small Semiometra-like ancestors in a brief Albian North American radiation, and suggest new interpretations of early comatulid phylogeny based on our findings. Adaptive allometry related to respiratory demands, along with an origin by peramorphosis, may explain some features of this odd, short-lived giant. The free-living, stalkless comatulids make up the bulk of living crinoid diversity and are the only crinoids remaining in shallow water, but compared to the stalked crinoids their fossil record is fragmentary and understudied, especially outside Europe. We present new Albian (113–100.5 million years old) fossil comatulids from the Glen Rose Formation, central Texas, and study their morphology and evolutionary relationships. New material comprises the previously described species Decameros wertheimi and Semiometra klari?, the new species Semiometra alveoradiata n. sp., and a new genus and species Castaneametra hodgesi n. gen. n. sp. In addition to being exceptionally variable, this species is the largest known comatulid, has the most cirri (claw-like appendages with which comatulids hold onto the substrate) of any known comatulid, and exhibits odd features otherwise unknown in comatulids. We infer how it lived and how it is related to other comatulids, argue for its origin from small Semiometra-like ancestors in a brief Albian North American radiation, and suggest new interpretations of early comatulid relationships based on our findings. Respiratory demands associated with large size, along an evolutionary lengthening of development time, may explain some features of this strange, giant new species.

Teff (Eragrostis tef cv. Moxie), a warm-season annual grass, could be an excellent forage for beef cattle. However, there is limited information on its nutritive value to cattle when harvested at different stages of maturity. Thus, the objective of this research was to determine the effect of feeding teff hay harvested at the boot (BT), early-heading (EH), or late-heading (LH) stages of maturity on nutrient intake, ruminal fermentation characteristics, omasal nutrient flow, and N utilization in beef cattle. Six ruminally cannulated beef heifers (mean initial BW ± SD, 476 ± 32.6) were used in a replicated 3 × 3 Latin square design with 28-d periods (18 d for adaptation and 10 d for measurements). Dry matter intake was measured daily. Indwelling pH loggers were used to measure ruminal pH from days 21 to 28. Ruminal fluid and omasal digesta were collected from days 26 to 28 to determine fermentation characteristics and omasal nutrient flow. Fecal and urine samples to quantify N excretion were also collected (days 26 to 28). Blood samples for plasma urea-N (PUN) determination were collected 3 h post-feeding on day 28. There were no changes (P > 0.28) in the ADF or NDF content of teff with advancing maturity, but indigestible NDF increased (P < 0.01) with increasing maturity. Maturity had no effect (P ≥ 0.14) on DMI, and ruminal total short-chain fatty acid (SCFA) concentration, pH, digestibility, and outflow of DM, OM, NDF, ADF, and CP. However, the CP content of BT hay was greater (P < 0.01) than for EH and LH hay (18.1, 14.1, and 11.5%, respectively, DM basis), and this resulted in the higher CP intake (P < 0.01) for heifers fed the BT than the EH and LH hay. Consequently, ruminal ammonia-N (NH3-N) concentration was greater (P < 0.01) for heifers fed BT than EH and LH hay, thereby possibly explaining the tendency for a decrease (P = 0.08) in PUN concentration, and a decrease (P < 0.01) in the excretion of total N, urine N, and urea-N (UUN) with advancing maturity. However, fecal N excretion (g/d) did not differ (P = 0.76). In conclusion, despite a decrease in CP intake and ruminal NH3-N concentration, feeding beef heifers EH and LH compared to BT teff hay did not compromise ruminal digestion and outflow of DM, OM, NDF, ADF, and CP, and microbial protein synthesis. Advancing maturity in teff hay also resulted in a decrease in the excretion of total N and urine N and UUN when fed to cattle.

Abstract The objectives were to determine whether cows previously classified during a postweaning test as either low or high residual feed intake (LRFI or HRFI) differed in BW, BCS, and winter grazing activity while consuming poor-quality forage. Thirty Hereford × Angus (LRFI = 16; HRFI = 14) 2-yr-old mid- to late-gestation cows (pregnant with second calf) grazed sagebrush steppe for 78 d beginning 29 September 2015. BW and BCS were collected before and after grazing. Five cows of each RFI classification were fitted with global positioning system (GPS) collars on 16 November 2015 with data collection commencing 3 d later and continuing for 25 d in a 323-ha pasture. The GPS units collected location coordinates every 2 min from which total daily travel distance (DTD) was calculated. Visual counts for bite rate were obtained from collared cows over 8 d. Coordinate data, daily bite rate, BW, and BCS were analyzed as repeated measures using a mixed model, which included RFI group, day, and RFI group × day as fixed effects and cow within RFI group as the random effect. Change in BW and BCS was analyzed by ANOVA with RFI group as the main effect. Cow BCS and BW differed for both day (P < 0.0001) and day × RFI (P < 0.05). Body condition was less (P < 0.05) in LRFI cows at the beginning (5.8 ± 0.13 vs. 6.2 ± 0.14 BCS), but similar (P = 0.67) to HRFI at the end of the study (4.6 ± 0.13 vs. 4.6 ± 0.14). BW among the RFI groups did not differ (P = 0.20) prior to going to range. However, BW-change and BCS-change differed (P < 0.05) between RFI groups. Not only did the LRFI cows lose less BW (−50.0 ± 5.41 kg vs. −66.6 ± 5.78 kg) over the trial, they also were less variable with respect to BW loss. Cows did not differ (P > 0.21) by RFI for DTD or bite rate, but day was significant (P < 0.0001) with cows increasing bite rate as the season of year progressed (55.2 ± 5.63 bites/min for day 4 vs. 84.8 ± 5.32 bites/min for day 21) and increasing DTD as snow storms occurred. Although LRFI cows were leaner than HRFI cows at the commencement of the project, they lost less BW in a late season rangeland environment.

The objective was to determine if low- or high-residual feed intake (LRFI or HRFI, n = 24 for each) Hereford × Angus cows on continuously or rotationally grazed rangeland altered their grazing behavior when provided a protein supplement in late autumn. Treatments included continuously grazed, control (CCON, n = 12); continuously grazed, supplemented (CTRT, n = 12); rotationally grazed, control (RCON, n = 12); and rotationally grazed, supplemented pastures (RTRT, n = 12). Cows in each treatment had grazing time (GT), resting time (RT), and walking time (WLK) measured for 2 years with accelerometers. Bite rate (BR) was also measured. Time distributions of GT and RT differed by year (p < 0.05), being influenced by colder temperatures in 2016. Cattle in 2016 spent more time grazing during early morning and late evening (p < 0.05) and rested more during the day (p < 0.05). In 2017, cattle in the CCON treatment walked more (p < 0.05) during early morning time periods than did the CTRT cattle, indicative of search grazing. All supplemented cattle had greater BR (p < 0.05) than control cattle in 2017. Cattle with increased nutritional demands alter grazing behavior in a compensatory fashion when grazing late-season rangelands.

The late Ann Molineux, Director of the Non-vertebrate Paleontology Laboratory (NPL), and I helped Linda write the first draft for the 2008 paper. Because Linda had done most of the work collecting and preparing these faunas, and had experience producing PowerPoint talks, she became the lead author on these four papers, and presented these at the GCAGS Meetings. In recognition of Linda's success during years of collecting, two fossil taxa have been named for her: a new crab genus, “Lindahomola longispina” (Garassino et al., 2019), and a new echinoid species, “Echinothuria mccallae” (Thompson, 2016). Linda's current areas of interest include preserved Oligocene, Eocene, and Cretaceous color-marked fossils, and Plio-Pleistocene bivalves with preserved fossil ligaments.

Deuterostomes are a morphologically disparate clade, encompassing the chordates (including vertebrates), the hemichordates (the vermiform enteropneusts and the colonial tube-dwelling pterobranchs) and the echinoderms (including starfish). Although deuterostomes are considered monophyletic, the interrelationships between the three clades remain highly contentious. Here we report, Yanjiahella biscarpa, a bilaterally symmetrical, solitary metazoan from the early Cambrian (Fortunian) of China with a characteristic echinoderm-like plated theca, a muscular stalk reminiscent of the hemichordates and a pair of feeding appendages. Our phylogenetic analysis indicates that Y. biscarpa is a stemechinoderm and not only is this species the oldest and most basal echinoderm, but it also predates all known hemichordates, and is among the earliest deuterostomes. This taxon confirms that echinoderms acquired plating before pentaradial symmetry and that their history is rooted in bilateral forms. Yanjiahella biscarpa shares morphological similarities with both enteropneusts and echinoderms, indicating that the enteropneust body plan is ancestral within hemichordates.

The objectives were to determine if previously classified, efficient (LRFI, low-residual-feed intake, n = 12 × 2 yr) vs. inefficient (HRFI, high-residual-feed intake, n = 12 × 2 yr) lactating 2-yr-old Hereford × Angus cows differed in grazing behavior, body weight (BW), body condition score (BCS), and calf weaning weight while grazing rugged rangeland pastures. Cows were fitted with grazing halters containing both an accelerometer and a global positioning system (GPS) data logger during June 14 to July 4, 2016, August 2 to 25, 2016, May 23 to June 12, 2017, and August 5 to 28, 2017. GPS data were recorded at 7-min intervals in 2016 and 4-min intervals in 2017 and accelerometer data recorded at 25 times/s. Grazing time (GT), resting, walking, bite rate (BR), daily travel distance (DTD), elevation, and slope were analyzed with a mixed model that included fixed effects of RFI group, day, and RFI group × day and cow within treatment as the random effect. Cow BW, BCS, and calf weaning weight were analyzed by analysis of variance with treatment as the main effect. There were no differences (P > 0.10) due to RFI detected for BW, BCS, or calf weaning weights. During periods of mild heat load (MHL), HRFI cows spent more (P < 0.05) time resting during the day at lower elevations (P < 0.05) than LRFI cows. During a 6-d period in spring with only 2 h MHL, HRFI cows grazed 1.7 h/d longer than LRFI cows (P < 0.05); commencing grazing earlier in the morning and extending the grazing bout later. During the summer with > MHL, LRFI cows grazed more than HRFI cows 18% of the time (P < 0.10). The HRFI cows had greater GT than LRFI cows only 3% of the time (P < 0.10) during summer. There was no difference (P > 0.10) in BR between HRFI and LRFI cattle. The DTD tended (P < 0.10) to be greater for LRFI cattle during summer 2017. Over all sample periods, HRFI had greater walking than LRFI 15% of the time and LRFI exceeded HRFI cattle for walking 3% of the time (P < 0.10). The greater walking for HRFI was assumed to be associated with more search grazing. Metabolic heat load on hot summer days for HRFI cattle is presumed to have contributed to differences observed in grazing behavior. These results suggest that lactating cows with low-RFI phenotypes appear to be better adapted to grazing rugged rangelands in late summer during periods of MHL.

Abstract The objectives were to determine if strategic supplementation of range cows in central Arizona with either two or four long acting (6 mo) trace mineral rumen boluses containing Cu, Se, and Co would: 1) decrease yearly calving interval; 2) increase cow body condition, milk production, or calf adjusted weaning weights; and 3) to see if any of the above traits varied by cow breed. There were 194 Hereford (H) and 132 Composite (CGC; 50% Red Angus, 25% Tarentaise, 25% Charolais) control cows, 173 H and 125 CGC 1X treated (2 boluses in late winter) cows, and 183 H and 117 CGC 2X treated (2 boluses in autumn and 2 in late winter) cows used over the 4-yr period. Cows were weighed and scored for body condition (1–9, 9 = fattest) in February, May, and September of each year. Milk production was determined by weigh-suckle-weigh on a subset of cows (n = 169) at an average of 50 d lactation. The outcomes were analyzed using a restricted maximum likelihood-based mixed-effects model that included the categorical, fixed effects of breed, bolus, and year with the interactions of breed × bolus, and breed × year. For adjusted weaning wt (WW), year × bolus was added. The random effect of cow was also included. Calving interval had only the breed × bolus interaction added to the main effects. Age of dam was added as a covariate to all models. Milk production used the same model as calving interval with the added covariate of postpartum interval. Cow body condition score and calf adjusted weaning weights differed by breed and treatment (P < 0.05) with WW being greater (P < 0.05) for calves from 2X cows than for control calves. Milk production differed by year (P < 0.0001) but did not differ by either breed or treatment (P > 0.05). Calving interval was 389 ± 2.7, 382 ± 3.2, and 378 ± 3.2 d for control, 1X, and 2X treatments, respectively and calving interval declined (P < 0.05) from the control to the 2X treatment group. Strategic supplementation via a long-acting trace mineral bolus was successful in decreasing calving interval and increasing calf-weaning weights from cattle grazed in an extensive rangeland environment.

Cows maintained on late-season rangeland in the Pacific Northwest often experience declining forage quality which may fail to meet protein requirements (7% of dry matter) necessary for adequate rumen function (Leng, 1990).