How to make rice healthier for you and the environment

Credit: Rob & Dani (CC BY 2.0)
Credit: Rob & Dani (CC BY 2.0)

What do congee, paella, risotto, and chimichangas have in common?

Rice.

Nearly half of the world’s population eats rice on a daily basis, making it a staple food for roughly 3.5 billion people. As delicious and filling as rice is, it is also the main source of arsenic for humans and its cultivation is one of the greatest contributors of methane emissions in the atmosphere. Two papers published last week in the journals PLoS ONE and Nature highlight the most recent efforts by researchers to find solutions for rice’s arsenic and methane problems. Continue reading

Hold your breath: carbon dioxide triggers exploratory behaviour in mosquitoes to help find hosts

A female mosquito feeding on a hapless victim.
A female mosquito feeding on a hapless victim.

Smack!

The tranquility of a lakeside sunset, disturbed by my attempts to stop bloodthirsty mosquitos from eating me as supper. I don’t know why mosquitoes think I’m a more appetizing meal than my camping companions but thanks to a new study, I now have a better understanding of how they hone in on targets such as myself.

Mosquitoes rely on a number of different cues to find their hosts. These include the heat and scents we emit, the humidity generated when our sweat evaporates and the carbon dioxide that we breathe out. What is less well known is how these different cues interact with and influence one another. For example, does sensing one cue help a mosquito pick up on other cues? That’s the question Dr. Michael Dickinson at the California Institute of Technology tried to answer. Together with colleagues at the University of Washington, his team showed that carbon dioxide triggers mosquitoes to explore visual elements in their environment, which in turn guides them to potential hosts.

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Science With Friends: on sexes and reproduction

What do scientists talk about when they get together? All sorts of random things. Welcome to the first installment of Science With Friends, a new series where friends write about science. I hope it is both entertaining and informative. Enjoy!

[Image: Praveer Sharma]
Female (left) and male (right) black-necked stilts showing moderate sexual dimorphism. (Image: Praveer Sharma)
Why do men and women exist? Why are there not just…people? Peace, dear reader—I’m not channelling Yoko Ono’s Twitter feed here, but addressing the biological question of why so many creatures (but not all!) are divided into male and female.

The simplest way to reproduce is to just make an identical copy of yourself. This is mainly how bacteria, the oldest and most numerous organisms on the planet, get it done. But plenty of more complex beings, such as plants and animals, can reproduce the same way, through cuttings, budding or other similar means. This asexual sort of reproduction has many advantages—there’s no need to wander around searching for a mate and all one’s tried-and-true genes get passed on, instead of taking a chance and ending up mixed and matched with some rando’s janky DNA.

Asexual reproduction does not result in absolutely unvarying organisms—there’s inherent randomness in the biochemical processes governing life and errant radiation or chemicals can also come by and scramble things. These generate genetic variation, on which the evolutionary processes of selection and drift can act. But this way is slow and conditions, whether they are climatic or pathogenic, can change fast. When a new critter comes along that wants to hitch a ride on you/feed on you/liquefy you from the inside out, it would helpful to have the tools to deal with it sooner rather than later. This is where grabbing some DNA from another individual of your species can come in handy—they just might have what you need to fend this threat off. This is sexual reproduction. Continue reading