What determines body size?

Aug 03, 2006

How does a growing organism determine what its final body size will be? In the moth Manduca sexta, also known as the tobacco hornworm and recognisable by its distinctive blue-green caterpillar, adult body size is largely determined at the end of larval life, when the caterpillar has reached it final weight and is about to metamorphose into a moth.

In a study published today in the open access journal Journal of Biology, Frederik Nijhout, from Duke University in Durham, USA and colleagues built a new mathematical model that allows them to predict the size of an adult moth, on the basis of three parameters: the initial weight of the juvenile caterpillar, its growth rate and the rate at which the effect of a developmental hormone decays.

These three factors are independent of each other and each of them is determined by many genes.

The regulation of body size is therefore the result of the interactions among many genes involved in many different processes. These processes are themselves strongly influenced by external factors such as temperature and nutrition and Nijhout et al.’s study therefore sheds light on how environmental and genetic factors can interact to determine final adult body size.

Their new model is likely to have broad applicability and could explain size variations in flies and other insects as well as in moths.

Source: BioMed Central Limited

Explore further: MSF fighting cholera outbreak in Tanzania refugee camps

Related Stories

Architects to hatch Ecocapsule as low-energy house

3 hours ago

Where people call home depends on varied factors, from poverty level to personal philosophy to vanity to community pressure. Ecocapsule appears to be the result of special factors, a team of architects applying ...

California farmers agree to drastically cut water use

7 hours ago

California farmers who hold some of the state's strongest water rights avoided the threat of deep mandatory cuts when the state accepted their proposal to voluntarily reduce consumption by 25 percent amid ...

Apple may deliver ways to rev up the iPad, report says

7 hours ago

MacRumors last month said that the latest numbers from market research firm IDC's Worldwide Quarterly Tablet Tracker revealed Apple stayed on as the largest vendor in a declining tablet market. The iPad ...

Recommended for you

MSF fighting cholera outbreak in Tanzania refugee camps

12 hours ago

Medical charity Medecins sans Frontieres (MSF, Doctors Without Borders) said Sunday it had launched emergency treatment centres in Tanzania, where thousands of Burundians fleeing unrest have been hit by cholera.

Cognitive impairment predicts worse outcome in heart failure

13 hours ago

Cognitive impairment predicts worse outcome in elderly heart failure patients, reveals research presented today at Heart Failure 2015 by Hiroshi Saito, a physiotherapist at Kameda Medical Centre in Kamogawa, Japan. Patients ...

Bacteria blamed in indigenous Mexican baby deaths

May 23, 2015

Bacteria—and not a contaminated vaccine as initially suspected—were to blame for the recent deaths of two Mexican babies and for sickening 29 others, according to an official investigation.

German woman, 65, gives birth to quadruplets

May 23, 2015

A 65-year-old teacher from Berlin has given birth to quadruplets after a pregnancy that was widely criticized by medical professionals because of her age, RTL television said Saturday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.