Collectors ‘prefer male species’

– Museum collections of birds and mammals may be disproportionately skewed to favour males, even if female members of the species outnumber males in the wild, according to research published yesterday.

Natalie Cooper, a researcher in the department of life sciences at the Natural History Museum in London, and her colleagues analysed the sex of almost 2.5 million specimens from five international collections, some dating back over a century.

Although as many as half of the bird specimens were not labelled by sex, of the ones that were, only 40% were female. Female mammals represented 48% of the collections identified by sex.

“We suspected that some bias towards males would be found because science is done by people,” said Cooper.

What surprised the researcher, though, was that there was no change in the ratios from collections dating back 130 years to more recent collections.

“In museums, collectors in the 19th century were mostly male, and though this is

Paris

changing, it’s still a male-dominated field,” she added.

Collection methods may be part of the problem. In some species, the males may be larger or showier, making them easier to spot and collect.

When scientists disproportionately collect male deer, for example, which are larger than their female counterparts, the specimens studied represent a larger average size than in the wild.

“By ignoring females we don’t get a full picture of life,” said Cooper.

Even when female specimens were larger or showier than males, the study found the median percentage of females was still only 44.6%. The same trend applied for male mammals with “ornaments”, such as horns, antlers or tusks.

But even in species where females also have ornaments, collectors preferred males. The trend carried over to bird collections, too. Male birds that are significantly more colourful or ornamental than females – birds of paradise, for example – were preferred by collectors, the author said. –

Jakarta

Mechanical and design issues contributed to the crash of a Lion Air 737 MAX jet last October, Indonesian investigators told victims’ families in a briefing yesterday ahead of the release of a final report.

Contributing factors to the crash of the new Boeing jet, which killed all 189 on board, included incorrect assumptions on how an anti-stall device called the Maneuvering Characteristics Augmentation System (MCAS) functioned and how pilots would react, the presentation showed.

The briefing slides showed that a lack of documentation about how systems would behave in a crash scenario, including the activation of a “stick shaker” device that warned pilots of a dangerous loss of lift, also contributed. “Deficiencies” in the