Invertebrate numbers have decreased by 45% on average over a 35 year period in which the human population doubled, reports a study on the impact of humans on declining animal numbers.
This decline matters because of the enormous benefits invertebrates such as insects, spiders, crustaceans, slugs and worms bring to our day-to-day lives, including pollination and pest control for crops, decomposition for nutrient cycling, water filtration and human health. (more…)
Pollination, essential to much of life on earth, requires the explosive death of the male pollen tube in the female ovule. In new research, Brown University scientists describe the genetic and regulatory factors that compel the male’s role in the process. Finding a way to tweak that performance could expand crop cross-breeding possibilities.
PROVIDENCE, R.I. [Brown University] — Millions of times on a spring day there is a dramatic biomolecular tango where the flower, rather than adorning a dancer’s teeth, is the performer. In this dance, the female pistil leads, the male pollen tubes follow, and at the finish, the tubes explode and die. A new paper in Current Biology describes the genetically prescribed dance steps of the pollen tube and how their expression destines the tube for self-sacrifice, allowing flowering plants to reproduce. (more…)
Every spring in the United States, bees pollinate crops valued at about $14 billion.
A Michigan State University professor and a team of scientists are using a five-year, $8.6 million grant from the United States Department of Agriculture to keep this winged workforce operating efficiently.
Almonds, strawberries, apples, cherries, blueberries, raspberries, watermelon, cucumbers and more depend on bees to help maximize yields. But with wild honey bee populations decimated by varroa mites and other threats, farmers are dependent on beekeepers to deliver managed colonies of honey bees during peak pollination to ensure their flowers are pollinated. (more…)
Creeping climate change in the Southwest appears to be having a negative effect on pinyon pine reproduction, a finding with implications for wildlife species sharing the same woodland ecosystems, says a University of Colorado Boulder-led study.
The new study showed that pinyon pine seed cone production declined by an average of about 40 percent at nine study sites in New Mexico and northwestern Oklahoma over the past four decades, said CU-Boulder doctoral student Miranda Redmond, who led the study. The biggest declines in pinyon pine seed cone reproduction were at the higher elevation research sites experiencing more dramatic warming relative to lower elevations, said Redmond of CU’s ecology and evolutionary biology department. (more…)
Pollination could be a chaotic disaster. With hundreds of pollen grains growing long tubes to ovules to deliver their sperm to female gametes, how can a flower ensure that exactly two fertile sperm reach every ovule? In a new study, Brown University biologists report the discovery of how plants optimize the distribution of pollen for successful reproduction.
PROVIDENCE, R.I. [Brown University] — Next Mother’s Day, say it with an evolved model of logistical efficiency — a flower. A new discovery about how nature’s icons of romance manage the distribution of sperm among female gametes with industrial precision helps explain why the delicate beauties have reproduced prolifically enough to dominate the earth.
In pollination, hundreds of sperm-carrying pollen grains stick to the stigma suspended in the middle of a flower and quickly grow a tube down a long shaft called a style toward clusters of ovules, which hold two female sex cells. This could be a chaotic frenzy, but for the plant to succeed, exactly two fertile sperm should reach the two cells in each ovule — no more, no less. No ovule should be left out, either because too many tubes have gone elsewhere, or because the delivered sperm don’t work. (more…)
Widespread reports of a decline in the population of bees and other flower-visiting animals have aroused fear and speculation that pollination is also likely on the decline. A recent University of Toronto study provides the first long-term evidence of a downward trend in pollination, while also pointing to climate change as a possible contributor.
ANN ARBOR, Mich. — Shade-grown coffee farms support native bees that help maintain the health of some of the world’s most biodiverse tropical regions, according to a study by a University of Michigan biologist and a colleague at the University of California, Berkeley.
