Mexican muralist artist Diego Rivera


This 8 December 2017 video is about Mexican muralist artist Diego Rivera.

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Mexico creates North America’s largest ocean reserve


This April 2017 video from Mexico is called 4K Underwater Video: Revillagigedo Archipelago (Socorro Islands) Scuba Diving.

From the BBC today:

Mexico creates huge national park to protect marine life

The Mexican government has created a large marine reserve around a group of islands home to hundreds of species including rays, whales and sea turtles.

The Revillagigedo Archipelago is a group of volcanic islands off the country’s south-east coast.

With a protection zone of 57,000 square miles (150,000km), it has become the largest ocean reserve in North America.

The move will mean all fishing activity will be banned, and the area will be patrolled by the navy.

It is hoped the move will help populations hit by commercial fishing operations in the area recover.

The park was designated by a decree signed by Mexican President Enrique Pena Nieto. It will also forbid natural resources being extracted from the land or the building of new hotel infrastructure.

The area, which is about 250 miles (400km) south-east of the country’s Baja California peninsula has been described as the Galapagos of North America, because of its volcanic nature and unique ecology.

Sitting on the convergence of two ocean currents, the islands are a hub for open water and migratory species.

It has hundreds of breeds of ocean wildlife, including humpback whales that use the shallow and coastal areas around the islands for breeding.

Last year the Pacific Ocean site was named as a UNESCO world heritage area.

María José Villanueva, the director of conservation of WWF in Mexico, described the move as an “important precedent” to the rest of the world, according to local media.

It follows a similar move by Chile, which created an even bigger ocean reserve in 2015.

Great white sharks off Mexico


This video says about itself:

3 November 2017

Ten years after filming Great White Sharks at Guadalupe Island in Mexico for the first season of Jonathan Bird’s Blue World, Jonathan and the team return to Guadalupe to see how it has changed. Are the sharks still there?

Saguaro cactus evolution, new study


This video from the USA says about itself:

Saguaro National Park

28 November 2012

Saguaro, Arizona — Home to America’s largest cacti, majestic plants, magnificent desert sunsets.

From the University of California – Berkeley in the USA:

Saguaro and other towering cacti have a scrambled history

Long lives of columnar cacti muddle scientists’ efforts to understand group’s evolutionary history

Summary: Biologists continue to debate the genealogy of the cactus family, even differing by a factor of 10 about how many different genera there are. A study based on new genome sequences of four columnar cacti, including saguaro and cardon, illustrates why this is. Because of the long lives of these columnar cacti, ancient genes drop out at random and give the impression of parallel evolution in those species that retain the genes.

Visitors to Mexico and the U.S. Southwest can’t help but stand in awe of the solitary and majestic saguaro, the towering clusters of the organ pipe cactus and Baja’s cardón, the appropriately named “elephant” cactus. The saguaro alone can grow to a height of more than 75 feet.

Scientists have now sequenced the complete genomes of four of these columnar cacti, and found, to their surprise, that their family relationships are not so straightforward as their shapes suggest.

According to Noah Whiteman, a UC Berkeley associate professor of integrative biology who is a coauthor of a paper appearing this week in the journal Proceedings of the National Academy of Sciences, the cactus family tree and the giant cacti in particular — the giant saguaro, organ pipe, senita and cardón, also called the Mexican giant cactus — have been very difficult to trace. Found only in the Americas, cacti have adapted to a broad range of environments, with a current count of 1,438 species. Yet scientists disagree by a factor of 10 about how many genera of cacti these species represent.

This is in part because the same traits — succulence and a columnar form, for example — seem to have evolved separately in different lineages: what’s known as parallel evolution.

In the study, led by Whiteman’s colleagues at the University of Arizona and the Universidad Nacional Autónoma de México, the scientists created individual family trees of each gene shared across all species. They found that their histories were scrambled as a result of long generation times — saguaro cacti can live 150 years or more — making it difficult to understand the relationships among the species even with complete genomic information.

They did determine, however, that some similarities, like the succulent flesh that makes some cacti a good emergency source of water, resulted from ancient genes that were retained by some cacti but lost by others. What looked like parallel evolution, with some species gaining new genes and new functions, was actually just the random loss of genes in all the other species.

The findings could have implications for the fate of these cacti, which are losing habitat because of human development in arid areas of the Americas.

“Many species are endangered, and the fact that we don’t understand their relationships makes this fraught,” said Whiteman, who is also a faculty member with the Center for Computational Biology and an affiliate of the University and Jepson Herbaria and the Museum of Vertebrate Zoology.

The work also addresses a recently recognized complication in interpreting the evolution of all plants and animals.

“Only with whole-genome sequencing were we able to see this pattern of incomplete lineage sorting, called hemiplasy, which looks superficially like convergent or parallel evolution, or homoplasy,” he said. “It’s an important advance because one could mistake such patterns as evidence for parallel evolution at the molecular level, which is a hot topic in evolutionary biology right now.”

Endangered vaquita porpoises of Mexico


This video is called Vaquita – Saving the Desert Porpoise.

From the National Marine Mammal Foundation:

Vaquita porpoise rescued as part of VaquitaCPR conservation project, then released

VaquitaCPR demonstrating success in locating endangered Vaquita Porpoises as field operations continue

October 23, 2017

Scientists with the VaquitaCPR conservation project and Mexico’s Secretary of the Environment Rafael Pacchiano announced they succeeded in locating and rescuing a highly endangered vaquita porpoise yesterday, but in an abundance of caution the vaquita, which was a calf, was released. Experts say the calf was being closely monitored by marine mammal veterinarians and showed signs of stress, leading to its release.

“The successful rescue made conservation history and demonstrates that the goal of VaquitaCPR is feasible,” said Secretary Pacchiano. “No one has ever captured and cared for a vaquita porpoise, even for a brief period of time. This is an exciting moment and as a result, I am confident we can indeed save the vaquita marina from extinction.

Experts had planned extensively for the scenario that unfolded on Wednesday and every precaution was taken to safeguard the health of the vaquita calf, which was estimated to be about six months old.

“While we were disappointed we could not keep the vaquita in human care, we have demonstrated that we are able to locate and capture a vaquita,” said Dr. Lorenzo Rojas-Bracho, a senior scientist with SEMARNAT, CIRVA and VaquitaCPR Program Director. “We also succeeded in transporting one and conducting health evaluations that are part of our protocols safeguarding the animals’ health.”

Scientists returned the vaquita calf to the same spot in the Gulf of California where it was originally located and where other vaquitas were observed. Before releasing the vaquita, various tissue samples were taken which scientists will analyze and share with colleagues at other research institutions like the Frozen Zoo in San Diego, California which will conduct genetic sequencing.

The precedent-setting rescue comes as the bold conservation plan led by the Mexican government (SEMARNAT) to save the endangered vaquita porpoise from extinction enters its second week of field operations. During the first three days, scientists spotted several vaquitas using visual search methods and acoustic monitoring. Vaquitas were repeatedly located by the VaquitaCPR ‘find’ team.

The vaquita porpoise, also known as the ‘panda of the sea,’ is the most endangered marine mammal in the world. Latest estimates by scientists who have been monitoring the vaquita for decades show there are fewer than 30 vaquitas left in the wild. The vaquita only lives in the upper Gulf of California.

Secretary Pacchiano has visited the VaquitaCPR facilities in San Felipe several times and accompanied scientists during a day of field operations on the Sea of Cortez. “The individuals involved in this unprecedented conservation project are the best in their respective fields,” said Secretary Pacchiano. “I’ve personally witnessed their dedication and incredible expertise. We’re all committed to saving the vaquita porpoise and this is the team who can do it.”

The project, which has been recommended by the International Committee for the Recovery of the Vaquita (CIRVA), involves locating, rescuing and then temporarily relocating the vaquitas to an ocean sanctuary off the coast of San Felipe. The explicit goal of CPR is to return the vaquitas to their natural habitat once the primary threat to their survival has been eliminated. Experts from all over the globe, including Mexico, the United States, Denmark, the Netherlands, Canada, New Zealand and the United Kingdom are all working together on VaquitaCPR.

VaquitaCPR field operations, including efforts to locate and bring vaquitas into temporary sea pens, began on October 12 and are expected to continue for several weeks. Windy conditions prevented VaquitaCPR field operations from taking place at sea for three days. When there are sustained winds of more than about eight knots, conditions on the water are too choppy for scientists to visually locate vaquitas. It also could risk the safety of vaquitas during the capture operation.

“We’ve unfortunately been at the mercy of the weather and were in the position of ‘waiting on the wind’ for several days,” said Dr. Cynthia Smith, VaquitaCRP Program Manager. “However, the time hasn’t been wasted, as there has been a tremendous amount of productive discussion at all hours of the day as we continue to refine the process of rescuing the animals. Now that we’re back on the water and conditions are better, the entire team is optimistic and working together seamlessly to support the mission.”

In an unprecedented move in April of 2015 that demonstrated Mexico’s commitment to conservation, President Peña Nieto announced a two-year gillnet ban throughout the vaquitas’ range, compensated fishermen and related industries for their loss of income, and enhanced multi-agency enforcement of the ban led by the Mexican Navy.

In June of 2017, the ban on gillnet fishing was made permanent. The government also launched an extensive survey of the vaquita population using an approach that included both visual monitoring and advanced techniques that use sound to locate the animals. All told, the Mexican government has committed more than $100 million in an effort to protect the vaquita and support the local fishing community.

A crucial part of CPR is the acoustic monitoring system that will help to locate the remaining vaquitas. This monitoring has been supported since 2012 by WWF and operated by the National Institute of Ecology and Climate Change of Mexico (INECC) to help estimate the vaquita’s population, and will continue during the CPR operations. WWF will also continue supporting the retrieval of lost or abandoned “ghost” nets, many of them illegal, which drift aimlessly and continue to entangle and kill vaquitas and other marine species. Both the acoustic monitoring and the net retrieval are conducted with the help and experience of local fishermen.

VaquitaCPR is led by Mexico’s Ministry of Environment and Natural Resources (SEMARNAT). The National Marine Mammal Foundation, Chicago Zoological Society and the Marine Mammal Center are primary partners in this extraordinary conservation effort.

VaquitaCPR operates as a private and public partnership, relying on both private donors and government funds. VaquitaCPR has many key collaborators including the National Oceanographic and Atmospheric Administration (NOAA) and groups like the Association of Zoos and Aquariums, Baja Aqua Farms, and Museo de la Ballena.

As part of VaquitaCPR, large floating sea pens will be anchored off the coast of San Felipe, where veterinarians and animal care experts will carefully monitor the health of any vaquitas that are successfully rescued. The sea pens have been designed and built by Baja Aqua Farms, a fish farm operation based in Ensenada.

The Museo de la Ballena’s mission is to promote the knowledge, study and conservation of cetaceans. Since the museum initiated a conservation operation last year, its vessel has succeeded in retrieving more than 900,000 linear feet of ‘ghost’ and illegal fishing nets. The museum is providing key logistical support for the VaquitaCPR team.

In order to make the Gulf safe for the vaquita in the future, experts agree it’s important to prevent illegal fishing of the also-endangered totoaba fish and to support alternative economies for the fishing community.

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.