Orchid embryo development is unusual among flowering plants with many distinctive characteristics. This review highlights the unique features of orchid embryos. After fertilization, the polarity is established in the zygote before its first asymmetric division. In species such as Epidendrum ibaguense H.B.K., the zygote elongates before the first asymmetric division, while others such as Cymbidium sinense (Andr.) Willd. divide without an apparent cell elongation phase. An obvious structural polarity with a prominent vacuole at the micropylar end is not necessarily present in orchid zygotes. The suspensor is derived from the basal cell of a two-celled embryo, and varied morphologies can be found. The suspensor functions in nutrient uptake and can have a morphogenetic role to play in embryo proper development. For embryos without an expanded suspensor, nutrients have to be acquired directly through their surface. The embryo proper develops from the terminal cell of a two-celled embryo. It undergoes a limited number of cell divisions resulting in a tiny embryo with a protocorm body plan. Despite their simple structural organization, orchid embryos have developmental programs as complex as other flowering plants. The ultimate goal of embryo development is to generate a protocorm body plan ready for germination.

Heliotropism of flowers is thought to provide a reproductive advantage to individuals of many species; yet, there are few clear demonstrations of a fitness advantage provided by heliotropism, most of which are almost completely restricted to plants from the arctic or alpine regions where a heat gain provides an advantage to the plants. In this study, we report heliotropism in the white trillium, an early spring blooming species from the temperate forests of eastern North America. The white trillium shows horizontal seasonal heliotropism with flowers mainly facing south throughout the summer, but it also exhibits daily horizontal and vertical heliotropism with the orientation of the flower tracking the sun during the day. The study of 479 tethered plants indicated that seasonal heliotropism provides a reproductive advantage to the white trillium, with south-facing individuals showing a 12% increase in fertilized ovules compared to north-facing plants. The ecology of this long-lived perennial is, in many aspects, similar to that of alpine and arctic heliotropic species. Indeed, white trilliums are insect-pollinated and they flower when the weather is cold, before the trees leaf out. This suggests that there are potentially more species for which heliotropism is advantageous amongst early spring flowers from the temperate forest.

Fisheries management relies on accurate population models for estimating biomass and setting harvest goals; however, physiological data for estimating reproductive parameters in population models are difficult to acquire. Here, lifetime reproductive (progesterone and estradiol) and stress-related (cortisol) hormones were measured in annually deposited growth increments in female yelloweye rockfish (Sebastes ruberrimus) opercula (N = 22 females, sampled ages 1–90 years). Analyses of these profiles (∼1-year resolution) provided estimates of physiological (complete puberty) and functional age of sexual maturity (females spawn and contribute larvae to the population) and spawning frequency, with lifetime trends of reproduction and stress. The descriptive mean age of physiological sexual maturity was 11 ± 1 years (standard error (SE)), whereas functional age of maturity was 17 ± 2 years. The estimate of marginal mean spawning frequency was 45.1% ± 5.1%. Stress data (∼15% of females experienced distress events) suggested that females were potentially resilient or not exposed to chronic stressors. Although preliminary, we provide a novel method to estimate age-specific reproductive parameters for proper age-based population modeling of a human-targeted teleost.

The purpose of this study was to determine whether postmeal walking (PMW, breaking up exercise into short bouts after meals) is an effective and feasible alternative to continuous walking for the management of gestational diabetes. Forty-one women with gestational diabetes were randomised between weeks 28–30 gestation to either standard care (30 minutes continuous exercise) or standard care with PMW (10 minutes of walking after breakfast, lunch, and dinner). Continuous glucose and activity monitors were worn to measure glycaemic control and adherence during 3 days of standard care (baseline) followed by 3 days of postmeal or continuous walking. A linear mixed model analysed the changes from baseline between postmeal and continuous walking, as an average of the 3-day periods. Thirty-two women (PMW n = 17: control n = 15, 33 ± 5 years, body mass index 25 ± 4 kg·m^–2) completed the trial. Postprandial and overnight glucose concentrations were similar between PMW and control; both interventions improved from baseline. There was no difference in adherence between groups; however, PMW completed more minutes of prescribed physical activity across baseline and intervention days compared to the continuous walking standard-care group. Preliminary findings from this proof-of-concept study suggest PMW could be a promising alternative to, and work interchangeably with, traditional advice to perform continuous moderate-intensity physical activity in women with gestational diabetes.

Determining the year-round spatial distributions of at-risk avian migratory species is critical for effective conservation. High-precision tracking enables the identification of distant breeding and nonbreeding areas and their connectivity, as well as migratory routes and associated threats. We GPS-tracked two groups of Eastern Whip-poor-wills (Antrostomus vociferus (A. Wilson, 1812)) that breed near the northern edge of their range, in Manitoba and northwestern Ontario (“west”), and in southern Ontario (“east”), Canada. The western-breeding birds were also ∼5° of latitude farther north than the eastern birds. We aimed to determine the degree of spatiotemporal overlap between the two groups during fall migration and at tropical wintering sites. We found that western-breeding birds departed earlier on migration than eastern-breeding birds, but we did not detect a difference in arrival timing to wintering sites. The two breeding groups retained spatial structure during migration, until all routes converged to circumnavigate the Gulf of Mexico. Western-breeding birds overwintered at sites farther south than eastern-breeding birds, consistent with a leapfrog pattern of migration. Quantifying the strength of migratory connectivity in at-risk species can be a first step toward defining breeding populations and informing customized conservation strategies throughout the annual cycle.