Biology And Cultural Importance Of The Narwhal

Cultural Importance of the Narwhal

• Multiple epistemologies, including Inuit-derived epistemology, are useful in investigating the narwhal and Arctic environment.
• Key Inuit approaches to knowledge:
  • Qaujimajatuqangit (IQ): "the Inuit way of knowing".
  • Isuma: "wisdom, to think, or thinking".
• IQ is an oral tradition passed down through generations, integrating multiple environmental variables and time-dependent decisions for survival.
• IQ includes mythology and dream interpretation, with respect for the environment and gratitude for its offerings.
• Technologies used in narwhal hunting, such as qamutik (Inuit sled) and qajait/qayaq (kayak), are designed for minimal environmental impact.
• Kayaks are tailored to individuals, considering size, weight, and arm reach, and designed for specific waters.
• Technology is respectful of the environment rather than attempting to control it.
• Forced relocation, colonization, and language oppression have interrupted the passage of knowledge between generations.
• Revitalization of Qaujimajatuqangit is ongoing, associated with a resurgence of Inuit culture and language.
• IQ is valuable for scientific advancement, requiring appreciation of Inuit values and recognition of past colonial efforts.
• Recent studies have broadened the applications of IQ in understanding narwhal anatomy, physiology, migration, and behavior.
• Formal recognition is necessary through collaborative efforts or Isumaqatigingniq to continue Inuit–scientist collaborations.

Scientific Approaches to IQ Integration

• Approaches range from no inclusion to full inclusion of perspective, contribution, and coauthorship.
• Few researchers fully appreciate and understand IQ’s potential importance.
• IQ integration is often directed at a specific research question and acknowledged with a sentence or citation, rather than full integration and recognition of Inuit contributors as authors or experts.
• Suggested guidelines are helpful before, during, and after incorporating IQ.
• Inuit postcolonial perceptions of scientists are often founded in mistrust.
• Valued awareness of IQ, and recognition and acknowledgment of Inuit insights and observations, will help reinforce the importance of collaboration.
• Opportunities for discoveries of Arctic science and narwhal biology are expanded greatly through collaborative efforts of science and IQ.

IQ Adds to Cultural and Scientific Studies

• IQ has benefited narwhal studies in migration, aggregation, dive patterns, acoustics, integrative and organismal biology, evolution, ecology, conservation, and tusk function.
• Historically, narwhals were viewed as curiosities for their tusks, worth more than 500 times their weight in gold, and used as antidotes for poisoning.
• Narwhals were celebrated in art such as Flemish tapestries like The Lady and the Unicorn and The Hunt of the Unicorn.
• Early Norse experiences with narwhals are believed to be informed by Inuit hunters.
• Modern literature focuses on establishing whale harvest quotas for sustainable populations, supported by migration and aggregation studies using electronic tagging.
• Recent biological literature includes genetic studies on diversity, evolution, climate science, COVID-19 transmission, and tusk sensory function.

Narwhal Migration and Population, Science, and IQ Perspectives

• The global narwhal population is estimated at 177,230, compiled from various regions:
  • Canadian Baffin Bay: 141,909
  • Northern Hudson Bay: 14,485
  • Greenland (Eastern): 6,444
  • Greenland (Western): 14,392
• In 2010, the total estimate was 80,000 (58,000–86,000 variation).
• Population models project declines due to climate change indicators, increased killer whale populations, and reduced prey availability.
• Inconsistencies in survey counts include the Admiralty Inlet population, estimated at 18,000 in 2010 and 35,000 in 2012.
• Population estimates have generally increased, but decreasing numbers were reported in Western Greenland, indicating a species at risk.
• Uummannaq narwhal hunter Pavia Nielsen presented Inughuit observations of increasing narwhal populations that contradicted scientific results at the 2006 Inuit Circumpolar Conference.
• A later study concluded low population numbers were due to survey methodology.
• The North Atlantic Marine Mammal Commission Scientific Committee confirmed that narwhal populations in Western Greenland were sustainable in 2012.
• Reports in 2015 indicated 766 narwhals were harvested from Canadian Inuit communities and 408 from Greenland communities.
• A moratorium on narwhal hunting in Canada in 2015, along with fishing limits, resulted from disputed population estimates.
• Nunavut Tunngavik Inc. and the Nunavut Wildlife Management Board challenged the findings with threats of a lawsuit.
• Difficulties with population estimates include:
  • Weather conditions prohibiting surveys.
  • Fixed point of reference issues.
  • Ice blockage.
  • Killer whales scattering narwhal groupings.
  • Population mixing.
  • Inaccurate aerial surface view calculations.
• Integrating IQ in the survey process has great potential.
• Active participation of Inuit hunters can improve the accuracy of scientific population estimates, as they monitor sightings across vast areas.
• The circumpolar Inuit possess a wealth of IQ that should be integrated into the scientific process.
• Inuit observations can augment and direct scientific studies.

IQ–Science Collaborative Benefits

• Collaboration with Inuit has greatly benefited knowledge of narwhal biology, climate change understanding, wildlife management, and Arctic marine mammal studies.
• IQ has been used to describe narwhal behavior, seasonal aggregations, migration, population, and anatomic variations.
• IQ–science collaborations include recognition studies of individual narwhal by skin markings, body, tusk morphology, and behavior.
• During a sassat/sikujjivik/sikujjaujut (ice entrapment) in Pond Inlet in 2008, Inuit recognized whales from Clyde River (410 km south).
• Inuit speculated seismic testing disoriented the whales.
• Other factors contributing to migration and distribution changes:
  • Climate change and global warming.
  • Killer whale predation.
  • Noise pollution from commercial development and shipping.
• Increased killer whale populations cause increased consumption loss.
• Narwhals' lack of a dorsal ridge gives orcas an evolutionary advantage.
• Narwhal dive times (20 min) are longer than killer whale dive times (11 min).
• Facial recognition software combined with IQ can better monitor changing migration patterns.
• Inuit hunters are sensitive to climate changes, noting population decreases or disappearances in some communities and increases in others.

Conservation and Anthropogenic Impact on Arctic Ecosystems

• Rapid detection and accumulation of plastics are additional environmental factors.
• Approximately 360 million tons of plastics are produced globally each year, with 19–23 metric tons mismanaged.
• The Arctic Ocean is the last stop of the North Atlantic Thermohaline circulation and North Pacific currents, leading to infiltration of plastics into Arctic food webs.
• Microplastics (<5 mm) are ubiquitous and easily incorporated into multiple trophic levels, binding heavy metals and persistent organic pollutants.
• Monitoring the impact of anthropogenic contaminants on narwhals through ocean currents, maritime activity, and mismanaged waste is crucial.
• Increasing ocean noise pollution (anthrophony) from human activity is a pressing conservation issue.
• Noise sources include ocean commercial and tourism-based vessel engine cavitation, seismic testing, and increased Arctic Ocean vessel traffic.
• Bulk vessel traffic increased by 160% in distance traveled from 2013 to 2019, with a 75% increase overall.
• Discoveries of mineral deposits and gas/oil reserves have led to more offshore commercial development and shipping noise.
• Greenland faces environmental concerns from commercial and tourism interests, balancing economic, social, and political interests with biodiversity.
• Ecotourism principles are often overlooked by economic investors, reminding Inuit of past colonial interests.
• Greenland's history includes Danish colonization, displacement of Inuit children, and seizure of hunting grounds.
• Economic incentives highlight alternative motives from cultural imperialism.
• Greenlanders want ecotourism developments balanced with sensitivity and respect for Inuit, Inughuit, and Greenlandic values.
• Future collaborations require respect to conserve the environment and sustain Inuit values.
• UN Sustainable Development Goal 12 calls for "responsible consumption and production."
• Seismic testing methods question this goal, impacting biodiversity (Goal 14).
• Scientifically and IQ-agreed recommendations should be followed to protect the Arctic Ocean environment.
• A noise pollution reduction subtarget would clarify this environmental concern.

Narwhal as a Model for Scientific Research

• Narwhals are recognized as extraordinary marine mammals, revered by the Inuit and subjects of fascination in art and science.
• Studies of the narwhal tooth sensory organ system are a useful model for research on other sensory organ systems (taste, smell, sight, sound, touch).
• Combined studies of narwhal physiology and anatomic systems (skeletal, muscular, nervous, renal, respiratory, endocrine, digestive, circulatory, reproductive, immune) are needed.
• Narwhal anatomy and physiology present extremes and outliers of evolutionary adaptation.
• Elucidating the digestive system may link to why whales are carnivores despite herbivorous ancestors.
• Understanding the high-frequency echolocation beam and unique fluke design is important.

Cetacean Evolutionary Background

• Cetaceans' evolutionary transformation is notable, originating from artiodactyls (even-toed ungulates) over 55 Ma during the Eocene era.
• Morphological adaptations enabled their transition from land to ocean.
• The fossil record documents changes from the Eocene (56–34 Ma), including spine reorientation, hind limb reduction, posterior nostril movement, underwater hearing, and tooth organ systems.
• Cetaceans are classified in the order Cetartiodactyla, including camel, pig, and hippopotamus.
• Molecular genetics show that hippopotamuses and whales share a common ancestor.
• Divergent parvorders of Odontoceti (toothed whales) and Mysticeti (baleen whales) are established from the fossil record and molecular genetic studies.
• Toothed mysticetes had pre-baleen structures in the Oligocene Epoch (24–34 Ma).
• Toothless mysticetes were prevalent dating back 30 Ma.
• Modern mysticetes progressed from toothed archeocetes to toothed plus baleen whales and extant baleen whales.
• Molecular genetic findings of inactive genes for ameloblastin and enamelin in extant mysticetes support this.
• The narwhal evolutionary pathway proceeds more directly from ancestral toothed whales.
• Lineages leading to modern cetacean families were present by the Middle Miocene.
• Delphinoidea (Monodontidae + Phocoenidae + Delphinidae) is well-supported, with Monodontidae related more closely to Phocoenidae.
• Crown delphinoids originated in the Early Miocene ($\overline{x}$ = 19.78 Ma; 95% CI: 18.81–20.76).
• Fossil lineages in the Kentriodontidae are tied to the early diversification of Delphinidae and Delphinoidea.
• Both crown Phocoenidae and crown Monodontidae originated in the Late Miocene.
• Additional investigation may link diverse artiodactyl links of evolution, demonstrated by the discovery of Arctic camels.

Systems Approach to Cetacean and Narwhal Physiology

• Whales have interesting biological adaptations in anatomy, physiology, and functional use.
• The systems approach to whale anatomy is useful in future studies of physiology and sensory function.
• The narwhal digestive system is multichambered, similar to herbivorous mammals, despite a carnivorous diet.
• Examination of digestive systems from three different populations indicates differing foraging patterns.
  • East Greenland: capelin from the pelagic ocean zone.
  • Northern Hudson Bay: shrimp and halibut from the benthic zone.
  • Baffin Bay: both benthic and pelagic prey.
• The reproductive system includes internalized organs (breasts, teats, penis).
• Whales lack an internal bone in the penis, similar to sea cows and humans, using elastic tissue instead of blood flow for rigidity.
• Whales retain a pelvis despite lacking hind limbs, which stabilizes the penis, controls the birthing canal, and assists in locomotion.
• Reproduction occurs tail first, equivalent to breach birth.
• Whales lack lips but use their tongue around a tube to dispense milk.
• The musculoskeletal system includes variable flipper forms, being more paddle shaped on narwhals, falcate on porpoises/dolphins, and elongated on finned pilot whales.
• Cetacean flippers can move in multiple planes and have the same humerus, radius, ulna, carpal, and phalange morphology as humans, with hyperphalangy for flipper extension.
• Hind limbs undergo gradual reduction, with rudimentary remnants in archeocetes like Basilosaurus, while narwhals have no hind limbs and a remnant pelvis.
• Cetacean spinal movements are complex and flexible, including yaw, pitch, and roll.
• Narwhal fluke design is consistent with most whales, but has a concave leading edge without sweepback.
  • Males have high efficiency at high speeds.
  • Females have increased lift and thrust at low speeds.
  • Lack of sweepback in males and increased efficiency may be associated with tusk drag.
  • Female fluke design is more efficient during deeper dives.
• Narwhal skeletal anatomy is best described through anatomical plates showing developmental and morphological adaptation with tusk expression and sexual dimorphism.
• The circulatory and cardiovascular system features veins that surround arteries for warming, and cooling veins release cool temperatures for sperm mobility.
• Veins and arteries can dilate or constrict for thermoregulation.
• Thin blubber in the tail fluke, flipper, and genital areas regulates heat.
• The odontocete respiratory system features one blowhole, unlike two in mysticetes.
• Blowhole shape is unique to each whale.

Evolutionary Adaptation of Sensory Organs

• Narwhal sensory organs elucidate evolutionary adaptation by exploring extremes and constraints of functional use.
• Limited vision and expanded auditory function are examples.
• Sound is recognized as crucial for narwhals.
• Mysticetes emit low-frequency sounds from the larynx, used for communication.
• Odontocetes use sound for navigation and prey tracking.
• Tusked narwhals need echolocation to navigate thin ice leads.
• Sound vocalizations are produced and emitted from phonic lips, filtered through fat bodies in the melon.
• Returning sounds are received by fat in the lower jaw.
• Sound reception from bone conduction is unlikely, as narwhal ears are separated from the skull.
• Narwhals have the most directional echolocation beam for orientation and foraging.
• An investigator experienced momentary numbness in the leg during hydrophone recordings, documenting the directed beam.
• Hair may be a sensory stimulus between a calf’s lips and a mother’s genital area for milking.
• Hair near the narwhal eye may transmit sensory signals regarding currents.
• The most studied sensory organ system is the erupted tusk and tooth organ system.
• Tusk function is primarily sensory, modeled after Brännström’s hydrodynamic theory of tooth sensitivity.
• Evidence includes:
  • High expression of sensory genes (Dlx2, FAM134B, NGFR, TFAP2A) in narwhal pulpal tissue.
  • Neuronal markers (CGRP and substance P) in pulpal tissue.
  • Patent dentinal tubules and channels within cementum allowing direct communication between the tooth sensory system and the ocean environment.
  • In vivo neurophysiological tusk perception to detect differences in high salt- and freshwater solutions.
• Research indicates primary sensory function is linked to sexual selection and reproductive fitness (mate choice or intersexual selection).
• Secondary considerations include establishing male hierarchy.
• New studies show unusual properties of tusk strength and flexibility.
• Young’s modulus and microhardness were measured using nano indentation with 200×100-µm spatial resolution.
• Mineral-to-collagen ratios decreased from tip to base and from the inner pulpal wall to the external surface.
• Narwhal tusk flexibility can bend 12° in all directions.
• Additional studies will advance understanding of unique narwhal evolutionary adaptation and functional tissue characteristics, potentially with biomimicry applications in medicine.
• Narwhals are intelligent animals, with brains containing more gray and less white matter.
• Paleontological studies can guide phylogenetic analyses; fetal membrane and uterine structures indicated artiodactyl origins as early as 1937.
• Synapomorphy (shared traits from a common ancestor) is another method for understanding phylogeny.
• Comparing paraxonic feet of cetaceans, hippopotamuses, and humans illustrates mammalian evolution.
• Homologous structures also suggest synapomorphy; narwhal tusk microstructure (patent dentinal tubules from ocean to dental pulp) is present in Odobenocetops tusks.
• Integrating biological studies of organ systems with genetic analysis will better understand narwhal biology.

Genomic Comparisons in Cetacean Phylogenetic Studies

• Phylogenetic comparisons benefit from increased variable base pairs, so highly resolved narwhal and beluga genomes can improve determination of their inferred relationship and shared Monodontidae family.
• Analyzing whole genomes (estimated 20,000 genes) reduces sampling errors.
• Comparative studies of beluga and narwhal should include genome content, gene order, gene orientation, and gene presence/absence.
• Elucidation of an ancestral genome provides insight to specific markers for mammalian diversity.
• Examination of noncoding sequences will elucidate the evolutionary path.
• Regulatory elements and noncoding RNAs can help determine critical points of evolutionary adaptation.
• Narwhal biology is strongly linked to the Arctic climate.
• Narwhals survived ice ages during the last 2.5 million years and the little ice age during the Holocene.
• Narwhal sediment remains indicate a similar distribution to today’s populations.
• Molecular signals show a common ancestor 6.3 million years before major cooling cycles.
• Narwhals should be able to adapt to global warming, as they did during the last interglacial period 125,000 years ago, but the Anthropocene adds human interaction.

Linking Genetics with Narwhal Disease Risk

• Genetic studies can predict viral infection rates for narwhals and other Arctic cetacean species.
• Collaborative efforts with Inuit hunters can assist early detection and diagnosis of diseases.
• Studies of SARS-CoV-2 transmission demonstrated high susceptibility and potential transmission to cetaceans, due to shared ACE2 spike protein binding sites.
• High Arctic communities were affected by SARS-CoV-2.
• Arctic mammals may become important in a chain of transmission.
• Toothed whales appear uniquely vulnerable to SARS-CoV-2, with a high binding propensity due to similar ACE2 amino acid sequences.
• Toothed whales have limited immune resistance to viral infection due to functional loss of GTPase genes MX1 and MX2.
• Gammacoronavirus has been found in beluga whales and bottlenose dolphins, and alphacoronavirus in harbor seals.
• Prior epidemics of phocine distemper virus caused over 50,000 deaths in harbor seals.
• ACE2 is significant in controlling blood pressure by converting AngI into AngII.
• Vasoregulatory peptides act on smooth muscle to change artery diameter and regulate blood flow.
• The marine mammal dive response involves blood pressure regulation; heart rate falls during submergence and constriction prevents a drop in arterial pressure.
• Genetic capabilities have enabled understanding and predicting changes to the ocean environment, anthropogenic variables, and potential threats to narwhals and other Arctic species.

Advancing the Process of Data Collection

• Methodology and data acquisition have changed dramatically over the past 50 years, from traditional specimen collection to remote imaging and sensing.
• Remote technologies can gather data over prolonged periods, benefiting Arctic research.
• Examples include cameras, motion detection video, light scanners, advanced drones, mobile PET/CT scanners, augmented reality, and artificial intelligence.
• Whale tags and remote-sensing devices measure dive depths, patterns, migration, acceleration, diet, habitat, salinity, temperature, sound recordings, navigation, communication, and heart rate.
• Hospital-grade equipment has been housed in waterproof casings for onsite analysis of brain activity and heart rate.
• Inuit observers are the most valuable remote-sensing resource, having unique connections to their environment due to survival needs.
• They hunt over longer seasons, observing extensively on the water.
• Inuit provide invaluable information on narwhal behavior and habitat.
• Skin molting was reported by Inuit hunters in Greenland, providing a reason for narwhal migration into freshwater inlets.
• Dive duration times observed by Inuit during hunting (45 min) exceed those reported in scientific literature (25 min).

Conclusion

• Ongoing studies are needed that combine IQ, social, political, conservation, remote-sensing, and scientific perspectives.
• The Arctic has succumbed to environmental disruption through pollutants, waste, noise, boat traffic, microplastics, and climate change.
• Narwhal populations are stable but face increasing environmental pressures.
• The rate of changes outweighs political capacity to address them.
• Engaging the Inuit in active monitoring and observation can balance environmental variables for survival.
• Scientists' most valuable remote-imaging/sensing instruments are the Inuit themselves, who are careful, consistent, and accurate observers of nature.
• Large, systems-based research teams benefit from new research tools combined with hundreds of years of IQ and Isuma.