Male Mexican fish prefer orange females


This video says about itself:

Valley of Silence: A refuge for Mexcalpique. Ocoyoacac, State of Mexico, Mexico

2 October 2017

The Valley of Silence is located at the national park Miguel Hidalgo and Costilla, better known as La Marquesa, in the municipality of Ocoyoacac, State of Mexico; Mexico. La Marquesa is located in the Central Plateau of Mexico, one of the largest mountain systems in the world that is considered by the Word Conservation Monitoring Center as one of the most important regions in the world for the conservation of fish freshwater as the main freshwater wetlands in the country with a unique fish diversity (Domínguez- Domínguez and Pérez-Ponce de León, 2007), in which goodeids are one of the most representative groups (Domínguez-Domínguez et al., 2006).

From ScienceDaily:

Do male fish prefer them big and colorful?

Male Mexican fish are attracted to females with large bellies

October 10, 2017

Male black-finned goodeid or mexcalpique fish know what they want when they pick a female to mate with; they prefer them big-bellied and as orange as possible. Interestingly, females displaying these traits are the ones most able to produce more offspring that survive, two researchers from the National Autonomous University of Mexico have found. The study by Marcela Méndez-Janovitz and Constantino Macías Garcia is published in Springer’s journal Behavioral Ecology and Sociobiology.

The black-finned goodeid (Girardinichthys viviparus) from Mexico is a very promiscuous species of fish, with males constantly seeking a suitable partner to mate with. The females are only sexually receptive for a few days every two months after giving birth. The black-finned goodeid is viviparous, meaning that young fish fully develop inside the female’s body before they are born.

During courtship, males concentrate all their attention on only one female at a time. The wooing process is made even harder because females can be quite selective. Courtship consists of three basic elements, and is initiated when the male approaches the female he has chosen. His interest is signalled through his dorsal and anal fins standing erect. He then folds these fins over the female’s body, in a type of embrace, before starting to swim in synchrony with her. The male will go on to occasionally attempt to grip the female more firmly and to copulate.

Méndez-Janovitz and Macías Garcia wanted to find out how male black-finned goodeid decide which female to single out for their attention. Ten males were held separately under laboratory conditions. Each one was presented with two pregnant females at a time for fifteen minutes. The females were photographed to catalogue their size, colouration and belly size. The researchers took specific note of how swollen the females’ bellies were, as an indication of the number of offspring that they could be carrying.

Some of the females were visited for more than five minutes at a time and the time males spent with a female went hand in hand with the specific physical traits that she possessed. Males lingered longer with the wider bellied, and more orange-looking females. They also made more displays with their fins erect towards ones that possessed such traits. In a further experiment, it was found that the larger females were the ones who produced more offspring that ultimately could survive better. Colour did not play a role in this.

“Belly area had the largest and most positive influence on male behaviour,” explains Méndez-Janovitz. “Males made longer visits and performed more courtship displays to the females with wider bellies, while spending less time with thin-bellied females. They also made a greater effort to court females with bodies of a more orange hue.”

“Some attributes of the females are therefore linked to their reproductive value, and seem to influence how much time and effort males devote to court them,” adds Macías Garcia.

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Monarch butterflies are in trouble


This video says about itself:

7 June 2016

The largest insect migration in the world ends each year in Michoacán, Mexico. Millions of monarch butterflies travel from the United States and Canada to pass the cold months in the towering trees of this beautiful forest. On their journey, the butterflies travel around 2,800 miles.

From the Entomological Society of America:

Damage to monarch butterfly colonies in 2016 storm worse than thought

Severe cold, snow, and high winds — and salvage logging that followed — weakened forest that protects declining butterfly

September 17, 2017

A much greater number of monarch butterflies perished in a snowstorm in March 2016 in Mexico than previously estimated, according to new research. Analysis of damage from the storm — and the ensuing salvage logging — sheds further light on the precarious state of the famed butterflies’ overwintering colonies.

Approximately 30-38 percent of the monarch butterflies (Danaus plexippus) in the Sierra Chincua and Cerro Pelón overwintering colonies died in the storm, says a team led by Lincoln Brower, Ph.D., research professor of biology at Sweet Briar College, far more than the estimated 7 percent mortality rate cited in initial media reports after the storm that struck between March 7 and March 11, 2016. The researchers’ findings are reported in the latest issue of the Entomological Society of America’s American Entomologist.

The storm was a severe combination of rain, snow, sleet, and hail along with strong winds and sub-freezing temperatures that downed several thousand Oyamel firs within the forests of the Monarch Butterfly Biosphere Reserve, declared a World Heritage Site by the United Nations in 2008. Typically, the dense forest creates a favorable “microclimate” for the monarchs, protecting them from exposure to intense winds, rain, and cold temperatures.

“The prolonged severe storm destroyed the normal microclimatic protection provided by the intact Oyamel forest and led to freezing in all the colonies,” Brower says. “This awakened us to the realization that the forest surrounding the butterfly colonies also needs to be protected, as a generalized wind buffer.”

Brower and colleagues counted dead butterflies in random plots within the colonies to estimate the total mortality rate from the storm: 31 percent in the Sierra Chincua colony and 38 percent in the Cerro Pelón colony. The true impact may still have been greater, however, as the researchers’ analysis of weather data from stations within and surrounding the Monarch Butterfly Biosphere Reserve, measured against existing research on monarch butterfly mortality in freezing temperatures, “support the conclusion that the March 2016 storm mortality … was substantially greater than 40 percent,” the researchers report.

Following the storm, the Mexican government permitted salvage logging to remove downed trees, due to concerns over potential fire or insect damage. Brower and colleagues argue, however, that the logging process was “profoundly disturbing and detrimental to the environment,” decreasing the forest’s ability to return to maturity and provide safe haven for the butterflies. A volume of 60,000 cubic meters of timber was approved for removal — equivalent to several thousand trees — which follows an incident of illegal logging occurring in the monarch reserve in 2015, reported in American Entomologist last year.

Brower was recently named a Fellow of the Entomological Society of America, in recognition of his career devoted to studying and raising awareness of the monarch butterfly and its overwintering colonies. Since the 1996-1997 overwintering season, the monarchs‘ colonies have declined in size by 90 percent. After more than 60 years, Brower’s work carries on, he says. “We hope to carry out a drone study, photographing the colonies from a standard height above the butterflies and then using photometric analysis to estimate changing colony densities,” he says. “We are concerned that the current methodology of reporting only total colony areas is underestimating the decline of monarchs overwintering in Mexico.”

Trump’s Mexican border wall threatens humans and wildlife


This video from the USA says about itself:

U.S.-Mexico Border Wall: Are Animals at Risk? | National Geographic

5 September 2017

President Trump’s plan to dramatically expand the border wall between the United States and Mexico has been subject to passionate debate, but one thing that’s certain is its detrimental impact on wildlife.

Like earlier border walls by, eg, George W Bush; and barbed wire around, eg, Hungary already do.

New giant sloth species discovery in Mexico


This video says about itself:

Fossil of New Giant Sloth Species Found in Underwater Cave | National Geographic

31 August 2017

In an underwater cave in the Yucatán in Mexico lie the well-preserved remains of an ancient giant sloth.

The new species is from the late Pleistocene. Its scientific name is Xibalbaonyx oviceps. Its scientific description is here.

Mexican singer Lila Downs, video


This video from the USA says about itself:

Mexican Singer Lila Downs in Conversation & Performance on Democracy Now!

29 June 2017

One of Mexico’s most acclaimed singer-songwriters, Lila Downs recently stopped by the Democracy Now! studio to perform four new songs and talk about her music, Donald Trump and much more. The Grammy-winning artist has just released her 10th album titled Salón, Lágrimas y Deseo. The album is dedicated to strong women everywhere.

New parrot species discovery in Mexico


The male of the new Amazona species. Photo credit: Tony Silva

From ScienceDaily:

Blue-winged Amazon: A new parrot species from the Yucatán Peninsula

The newly identified Blue-winged Amazon parrot has a loud, short call and evolved from the White-fronted parrot quite recently, about 120,000 years ago

June 27, 2017

In 2014, during a visit to a remote part of the Yucatán Peninsula in Mexico, ornithologist Dr. Miguel A. Gómez Garza came across parrots with a completely different colour pattern from other known species.

A study published today in the open-access journal PeerJ names these birds as a new species based on its distinctive shape, colour pattern, call and behaviour. The paper compares and contrasts the distinguishing features of this species with many other parrots.

The new parrot (Amazona gomezgarzai), referred to as the Blue-winged Amazon because of its primarily blue covert feathers, is characterized by its unique green crown that contrast to blue in other Amazon parrots. This new parrot occupies a similar area in the Yucatán Peninsula as the Yucatán Amazon (A. xantholora) and the White-fronted Amazon (A. albifrons nana) but it does not hybridize with them.

A very distinctive feature of the new taxon is its call, which is loud, sharp, short, repetitive and monotonous; one particular vocalization is more reminiscent of an Accipiter than of any known parrot. The duration of syllables is much longer than in other Amazon parrot species. In flight, the call is a loud, short, sharp and repetitive yak-yak-yak. While perched, the call is mellow and prolonged.

This species lives in small flocks of less than 12 individuals. Pairs and their offspring have a tendency to remain together and are discernible in groups. Like all members of the genus Amazona, this parrot is a herbivore. Its diet consists of seeds, fruits, flowers and leaves obtained in the tree canopy.

The analysis of mitochondrial DNA genes indicates that the blue-winged Amazon has emerged quite recently, or about 120,000 years ago, from within the A. albifrons population. During this time, the taxon differentiated sufficiently to be clearly recognizable as a new species.

There is no conservation program currently in effect to preserve this parrot but its small range and rarity should make its conservation a priority.