• This field is for validation purposes and should be left unchanged.
  • Earth.Org Newsletters

    Get focused newsletters especially designed to be concise and easy to digest

  • This field is for validation purposes and should be left unchanged.
SHOP Support

The Chocó, a cradle of biodiversity in western Ecuador, is the fourth most important hotspot for biodiversity in the world. The coastal tropical rainforest of the Chocó once stretched unbroken from southern Colombia to northern Ecuador. Despite devastating clearance, the forests that survive hold innumerable species of plants and animals, many of which are unique to this region. The Save the Chocó Campaign by Fundación Jocotoco, an Ecuadorian conservation non-profit, seeks to raise USD$5 million to purchase and protect 57 000 acres of pristine rainforest in the Chocó. 

The land purchase by Fundación Jocotoco would connect several existing reserves through the expansion of its Canandé Reserve (currently 18 500 acres) in the Chocó. This purchase would create a fully contiguous protected area of more than 740 000 acres – larger than Yosemite National Park in California and significantly larger than any protected area in Western Ecuador. Connecting these reserves would ensure that the last large population of jaguars will continue to roam the forests of Western Ecuador.

The newly protected area would cover a very large altitudinal gradient from sea level to nearly 5000m, higher than any peak in the continental US. This is the only site on the west slope of the Tropical Andes where the entire gradient of ecosystems can be protected. This large gradient is important to achieve climate change mitigation as it would allow wildlife to shift their ranges with increasing temperatures. Moreover, this purchase would create a buffer zone for the indigenous Chachi Reserve and thereby help to preserve the forest the Chachi culture depends on. 

You might also like: Endangered Wildcat Kittens Born At UK Wildlife Park

Unfortunately, the only credible buyers for these properties are palm oil companies. Almost all of the forest west and south of Canandé Reserve has been cleared for oil palm plantations, releasing an estimated 2.12 million tons of greenhouse gases annually. The project would prevent the emission of more than 10 million tons of greenhouse gases. 

The survival of at least eight critically endangered species depends on this campaign, including the Brown-headed Spider Monkey, one of the 25 most threatened primates on the planet. 

The Chocó rivals the Amazon in terms of diversity of species but is far more threatened with only 2% of primary lowland rainforest remaining and an annual deforestation rate of 2.5%. Very little of the Chocó has been explored and there is a possibility that many species have yet to be discovered. Ten amphibians and reptiles that are found in the region await species description; they are so rare that they have not been found elsewhere. 

Featured image by: Flickr

About Fundación Jocotoco

Fundación Jocotoco is an Ecuadorian non-profit organisation whose mission is to protect the most threatened species and habitats in Ecuador. For more information, visit www.jocotoco.org. Donations are fully tax-deductible and will be matched up to USD$400 000. For questions, email: martin.schaefer@jocotoco.org

Formal definitions for “biodiversity” vary widely, but its purpose in measuring the variety of life is relatively uncontroversial. Emphasising the aspects of species richness and abundance, biodiversity is overwhelmingly concentrated in the tropical ecosystems of rainforests, savannas, freshwater bodies and shallow-water coral reefs, where over three-quarters of all known non-marine species can be found. Why is this? Amongst numerous proposed explanations, factors of high net primary productivity (NPP), spatial heterogeneity and niche conservatism hypothesis will be examined.

tropical ecosystems biodiversity
Proportion of species found within tropical latitudes for ten taxonomic groups (Source: Barlow et al. 2018). 

High NPP in tropical regions allow them to sustain larger communities with wider varieties of species, as easily observed from the sheer abundance of observable plant biomass in the tropics. The figure below illustrates how mean annual NPP near the equator (at 0° latitude) is approximately double that of temperate zones (between 35°-50°), while demonstrating the negative correlation between NPP and absolute latitude. With increased energy availability at lower latitudes, tropical habitats can support more species with minimum viable populations, contributing directly to α-diversity (alpha-diversity, the mean species diversity within a habitat at a local scale). Furthermore, greater ecosystem carrying capacity could also translate to enlarged populations of various organisms. Holding mutation rate constant per individual, bigger populations would increase frequency of mutations and hence genetic variation within a species. Beyond reducing their susceptibility to extinction, intraspecific genetic variation is also an important precursor for speciation to occur.

You might also like: 50% of Earth’s Land Surface Remains Relatively Untouched By Humans

tropical ecosystems biodiversity
Comparison of the latitudinal distribution of the median (solid line), and 10th and 90th percentiles (dotted lines) of area-weighted mean annual net primary productivity (Source: Kicklighter et al. 1999)

Without undermining the importance of energy abundance, it is spatial heterogeneity within the tropics which set the stage for speciation to take off, by partitioning resources more effectively while favouring further niche specialisation. For speciation to arise from intraspecific genetic variation, limited or complete segregation of deviating individuals (those individuals with differing characteristics from the average member of the same species) is required, until sufficient divergence of characteristics has occurred to ensure reproductive isolation. In tropical rainforests, stratification of vegetation into the forest floor, understorey, canopy and emergent layers helps facilitate these processes. 

A study conducted in the Bornean rainforest of Kinabalu Park revealed that concentration of flower-visiting butterflies increased towards the canopy where flower availability was highest, while fruit-feeding butterflies mainly reside in the understorey where rotting fruits are more common. Differing physical characteristics were also observed across the vertical gradient, with forewing length of butterflies decreasing at greater heights, since smaller body sizes are advantageous near the canopy to avoid being preyed on by insectivorous birds. 

Additionally, organisms themselves can become niches or resources for exploitation by others. Large old trees are especially well-known for providing microhabitats ranging from leaf litter to tree crowns, allowing organisms in tropical biomes to specialise and establish their own ecological niches separately from other individuals within the same species. Replicated over multiple generations, differences in intraspecific genetic composition then gives rise to formation of new species along these environmental gradients, bolstering β-diversity (beta-diversity, the change in species composition along an environmental gradient or across ecosystems. It is commonly measured along changing elevation on a mountain slope, or differing wetness of soil as we get closer to a river bank) in tropical ecosystems through means which are less prominent at higher latitudes, as temperate and polar region don’t have as many micro-habitats for deviating individuals to isolate and form new species along environmental gradients.

Given the numerous existing species with tropical origins, their limited expansion to higher absolute latitudes has been instrumental in preserving the relative species richness near the equator. Climatically stable tropical biomes have existed for lengthier geological timescales, whereas those further from the equator tend to be plagued with fluctuating temperatures and rainfall intensity. Consequently, more evolutionary lineages from the former managed to persist till the modern-day. The niche conservatism hypothesis aims to explain why tropical biodiversity seems largely restricted to their native geographies, by theorising that ancestral ecological preferences by different species would be preserved across time and space. This was empirically proven in a recent meta-study which concluded that species originating in warmer climates had steeper slopes of latitudinal diversity gradients, demonstrating significant affinity for tropical habitats. The poor survivability of tropical organisms in harsher environments- as in, those that experience extreme hot/ cold temperatures or those with low precipitation- is aggravated by their vast opportunities for specialisation within their native habitats, which allowed species to develop narrow ecological niches. Conversely, colder or more volatile environments may favour survival of generalist species with broader ecological niches for their adaptability to changing seasonal patterns. Consequently, these species may have experienced greater success during migrations towards the equator, further contributing to already-high tropical biodiversity. 

There are several key reasons for high biodiversity in tropical ecosystems. High NPP directly contributes to α-diversity by supporting more species with minimum viable populations, whereas enlarged populations of each organism increase overall mutation frequency and hence intraspecific genetic variation. Spatial heterogeneity within these habitats promote resource partitioning and niche specialisation. Continued reproductive isolation and divergence of deviating individuals from parent populations thus set the stage for intraspecific genetic variation to develop into new species along environmental gradients, enhancing β-diversity of these ecosystems. Finally, the niche conservatism hypothesis explains why tropical organisms remain largely restricted to their geographical origins, hence preserving the relative biodiversity richness of tropical ecosystems. A holistic understanding of contributing factors for hyperdiversity is essential to evaluate the challenges faced by these ecosystems amidst anthropogenic climate change.

New Guinea has the highest plant diversity of any island on Earth, reports a comprehensive assessment of vascular plant species published in the journal Nature. The species list, which was compiled by 99 botanists from 56 institutions across 19 countries, verified the identity of over 23,000 plant names from over 704,000 specimens collected from New Guinea since the 1750s.

The research concludes New Guinea has 13,634 species of plants from 1742 genera and 264 families. That gives New Guinea, the world’s second largest island, the highest plant diversity of any island on Earth, surpassing Madagascar (11,832 species), Borneo (11,165 species), and Sumatra (8,391 species). New Guinea ’s plant diversity is greater than that of the entire archipelago of the Philippines (9,432 species).

Just five families account for more than a third of plant species on the island. Orchids, with 2,856 species or 21% of the island’s species, are the most diverse.

There are 3,962 species of trees in New Guinea or about four times the number found across all of North America.

New Guinea’s flora is also highly unique. The study finds that more than two-thirds of its plants are endemic, meaning they are only found on the island. New Guinea’s high degree of endemism is “unmatched in tropical Asia” according to the researchers.

“New Guinea is extraordinary: it is a paradise island teeming with life,” said the paper’s lead author, Rodrigo Cámara-Leret of the University of Zurich, in a statement. “As the second largest island in the world after Greenland and the world’s largest tropical island, it supports a mosaic of ecosystems and is globally recognized as a centre of biological diversity.”

“However, despite this, knowledge on New Guinea’s flora has remained scattered for years, limiting research in this megadiverse area. Our paper set out to address this.”

You might also like: New Penguin Colonies Discovered in Antarctica, Increasing Numbers by 20%

new guinea plant diversity
The genus Freycinetia, with 140 species, is a group of forest climbers in the Pandanaceae family, one of the 20 most diverse groups in New Guinea. Photo Royal Botanic Gardens, Kew for Mongabay. 

Prior to this paper’s publication, the estimates of the number of species on New Guinea ranged from 9,000 to 25,000. The Global Biodiversity Information Facility, an international research initiative backed by governments and organizations, lists nearly 30,000 species for Papua New Guinea alone, far exceeding the 10,793 species verified by the new study. Improving the accuracy of the number of plant species is critical for efforts to conserve the island’s flora, say the researchers.

“It is clear, in the context of the biodiversity crisis, that this paper represents a milestone in our understanding of the New Guinea flora and provides a vital platform to accelerate scientific research and conservation,” said study co-author Peter Wilkie of the Royal Botanic Garden Edinburgh. “Research at its best is collaborative and this demonstrates what can be achieved when scientists from around the world work together and share expertise and data.”

The data is the product of more than 15,000 collections gathered from the wilds of New Guinea over the past 260 years. The island’s complex topography — including dramatic mountain ranges, deep valleys, alpine grasslands, and dense lowland rainforests — have made collecting expeditions more perilous than almost any place on Earth. Accordingly, botanists are still discovering new species at a rapid pace: more than 2,800 species have ben described in the past 50 years.

“Species discovery shows no sign of leveling off,” the authors write, noting they expect another 4,000 species to be described in “The Last Unknown” in the next half century.

But time may be running short for New Guinea’s biodiversity, since 2002 the island lost 1.15 million hectares of primary forest and nearly 2 million hectares of total tree cover. Papua New Guinea accounted for 53% of tree cover loss during that period. Logging, conversion of forests for plantations and small-scale agriculture, and fire are threats to the island’s native biota.

New Guinea’s high degree of endemism makes its flora particularly vulnerable, according to the paper. Deforestation of a single mountainside or valley could result in the extinction of species limited to that specific place.

“Such high richness of endemic species means that both countries have a unique responsibility for the survival of this irreplaceable biodiversity,” the authors write. “Given the general trend of plant endemism to increase with elevation, the conservation of ecosystems along altitudinal gradients is particularly critical.”

But the researchers believe their work will provide much more than just an inventory of what’s being lost in New Guinea.

“Our work allows us to understand what exists, and with that knowledge we are better equipped to conduct more informed science and applied conservation planning,” the University of Zurich’s Cámara-Leret told Mongabay via email. “Having a list verified by the leading New Guinea botanists will be essential for many branches of science. For example, having accurate names is essential for conservation planning as for understanding the potential impacts of climate change on biodiversity. Usually, modelers integrate lists of species and geographic occurrences with climate data. But if species’ names or geographic distributions are wrong, then the results can be very misleading.”

Cámara-Leret said that several of the study’s authors are working closely with the local government of Indonesia’s West Papua province to help identify priority areas for conservation.

“This is part of a grand vision by the local governor to conserve 70% of the forests of West Papua, as explained in the Manokwari Declaration,” he said. “As part of our research, we have been looking into the potential impacts of climate change on biological, but also cultural heritage.”

This rich cultural and biological (plant) diversity is what makes New Guinea so unique. Study co-author Tim Utteridge at the Royal Botanic Gardens, Kew, says that helping protect it should be of prime concern.

“I have been working in Indonesia for over 20 years and have always been fascinated by the beautiful and bountiful biodiversity of New Guinea,” Utteridge said in a statement. “We all now have a unique responsibility for the survival of this irreplaceable biodiversity.”

This article was originally published on Mongabay, written by Rhett A. Butler, and is republished here as part of an editorial partnership with Earth.Org.


Despite the global economic slowdown as a result of the COVID-19 pandemic, deforestation in the Amazon in Brazil is increasing rapidly, having risen for 13 consecutive months relative to year-earlier figures and reaching the highest level since monthly data started being released publicly in 2007, according to official data released by the country’s national space research institute, INPE. 

The institute’s deforestation monitoring system, DETER, detected 406 sq. km of forest loss in the ‘legal Amazon’ during April, bringing the overall extent of deforestation measured by the system to 9 320 sq. km for the year ended April 30, 2020, 40% higher than a year ago and more than double the level it was in April 2018.

Since the ‘deforestation year’ began on August 1, 2019, 5 606 sq. km of forest have been lost, the highest on record for this time of year.

Deforestation in the region, representing nearly two-thirds of the entire Amazon rainforest, has been increasing steadily since 2012, when 4 571 sq. km of forest were lost. Prior to this, deforestation had been declining because of better monitoring and environmental law enforcement, public and private sector efforts to curb deforestation and the creation of new protected areas and indigenous territories.

You might also like: Tropical Forests Are Losing Their Ability to Store Carbon

Amazon Deforestation Graph

deforestation amazon surge
Data from the INPE showing monthly deforestation alerts in the Brazilian Amazon since January (Source).  

According to a 2014 study, the drop in deforestation in the region between 2004 and 2013 avoided the GHG emissions equivalent of taking all cars off US roads for three years– 3.2 billion tonnes. 

Causes of Deforestation in the Amazon

The rise in deforestation has been noticeably higher since President Jair Bolsonaro came into power in January 2019. Bolsonaro is a notable anti-environmentalist, evidenced by him rolling back environmental regulations, granting amnesty from fines for illegal logging, cutting budgets for environmental law enforcement and disregarding the role of scientists in the government, blaming environmental NGOs for deforestation, claiming without evidence that actor Leonardo DiCaprio funded last year’s fires in the Amazon and opening protected areas and indigenous territories for extractive industries and agribusiness. 

Bolsonaro encourages deforestation in the Amazon, calling it a way to lift the region out of poverty. His administration has also sacked officials charged with protecting forests and indigenous people against illegal land invasions.

Brazil has now deployed thousands of soldiers to protect the rainforest due to concerns about the surging levels of deforestation ahead of the country’s high season for forest fires. The decision to deploy troops was made three months earlier than in 2019. 

The government says that the operation has begun in a national forest in Rondonia state, near the Bolivian border, with 3 800 soldiers. 

The military is currently authorised for deployment until June 10 but it could be extended as the dry season approaches, when forest fires tend to spread. 

The government has said that the armed forces would continue to be used until environmental agencies, such as the enforcement agency Ibama, increase their staff. Budget restrictions and an economic downturn has prevented Ibama from hiring any new agents. 

Last year, fires in the Amazon made international headlines when NGOs, human rights groups and business and political leaders called for boycotts of Brazilian companies and products, which prompted Bolsonaro to mobilise the army to help with fire-fighting efforts. Yet, he continues to push policies that will increase deforestation and fires nonetheless. 

Scientists warn that the entire biome may be nearing a tipping point where large areas of wet rainforest could transition to dry tropical woodlands and savanna. New research says that the Amazon could turn into a source of carbon instead of one of the biggest absorbers of the gas as soon as the next decade as a result of the damage caused by increasing deforestation in the Amazon, illegal loggers and the climate crisis. 

It is bizarre and dangerous that the Brazilian administration has such a wanton disregard for the health of the Amazon rainforest. There is plenty of evidence that economic growth need not come at the expense of the environment and in fact, research suggests that renewable energy could in fact spur economic growth post- COVID-19. It is imperative that global leaders continue to pressure the Brazilian government to do more in curbing deforestation, or the health of the planet will be at stake. 

Featured image by: Ibama

Subscribe to our newsletter

Hand-picked stories once a fortnight. We promise, no spam!

Instagram @earthorg Follow Us